* Remove `matrix_key_count()`

* Remove `matrix_bitpop()`

When helix/rev2 was using split_common, it didn't work properly and I couldn't type on the right hand side.

The cause is that the following code, added in 0.16.0 to `quantum/keyboard.c`, does not include `quantum/split_common/split_util.h` but instead includes `keyboards/helix/rev2/split_util.h`. Therefore, `split_pre_init()/split_post_init()` in `quantum/split_common/split_util.c` was not called.

```c
  #ifdef SPLIT_KEYBOARD
  #    include "split_util.h"
  #endif
```

```diff
  --- a/keyboards/helix/rev2/local_features.mk
  +++ b/keyboards/helix/rev2/local_features.mk
  @@ -6,7 +6,7 @@
   #

   KEYBOARD_LOCAL_FEATURES_MK :=
  --include $(strip $(HELIX_TOP_DIR)/pico/override_helix_options.mk) ## File ded  icated to maintenance
  +-include $(strip $(HELIX_TOP_DIR)/rev2/override_helix_options.mk) ## File dedicated to maintenance
  ```

* add licenses message to helix/rev2 files

* Minimize the processing of helix/rev2/local_features.mk

* Changed helix/rev2 default setting to use split_common

* fix helix/rev2:edvorakjp build error

* Remove unnecessary '#include' from keymap.c

* helix keymaps Workaround for build errors. five_rows_jis, fraanrosi, froggy, froggy_106, yshrsmz

* Revert "fix helix/rev2:edvorakjp build error"

This reverts commit 731dbbe151.
Separated into a single PR #16433.

* Revert "Changed helix/rev2 default setting to use split_common"

This reverts commit e76dbd7762.

* add 'SPLIT_*_STATE_ENABLE' into helix/rev2/config.h

* Revert "helix keymaps Workaround for build errors. five_rows_jis, fraanrosi, froggy, froggy_106, yshrsmz"

This reverts commit 9b316c1c6a.

* change helix:default to use split_common

* change helix:five_rows to use split_common

* add comment into helix/rev2/rules.mk

* change helix:led_test to use split_common

'helix/rev2/keymaps/edvorakjp' was no longer buildable due to changes made by #14864.
The reason is that the prototype of `oled_task_user()` was changed in keymaps/edvorakjp/oled.c, but keymaps/edvorakjp/oled.h was not changed.
Therefore, I modified the prototype in keymaps/edvorakjp/oled.h.

* Remove unnecessary backslash-escapes in default keymaps

* Remove unnecessary backslash-escapes in via keymaps

* Remove unnecessary backslash-escapes in default-ish keymaps

* [Core] Add kb level callbacks to OLED driver

* Update keyboards and keymaps

* Update docs

* Update userspace configs

* Add fix for my keymap ...

* update lefty

* Remove unused IS_COMMAND() instances from keyboard-level config.h, 0-9

* Remove unused IS_COMMAND() instances from keyboard-level config.h, A-B

* Remove unused IS_COMMAND() instances from keyboard-level config.h, C-D

* Remove unused IS_COMMAND() instances from keyboard-level config.h, E-G

* Remove unused IS_COMMAND() instances from keyboard-level config.h, handwired

* Remove unused IS_COMMAND() instances from keyboard-level config.h, H-M

* Remove unused IS_COMMAND() instances from keyboard-level config.h, N-R

* Remove unused IS_COMMAND() instances from keyboard-level config.h, S-Z

* Remove unused Magic Key definitions from keyboard-level config.h, 0-9

* Remove unused Magic Key definitions from keyboard-level config.h, A

* Remove unused Magic Key definitions from keyboard-level config.h, B

* Remove unused Magic Key definitions from keyboard-level config.h, C

* Remove unused Magic Key definitions from keyboard-level config.h, D-E

* Remove unused Magic Key definitions from keyboard-level config.h, F-H

* Remove unused Magic Key definitions from keyboard-level config.h, handwired

* Remove unused Magic Key definitions from keyboard-level config.h, I-K

* Remove unused Magic Key definitions from keyboard-level config.h, L-M

* Remove unused Magic Key definitions from keyboard-level config.h, N-R

* Remove unused Magic Key definitions from keyboard-level config.h, S-V

* Remove unused Magic Key definitions from keyboard-level config.h, W-Z

* Merge remote-tracking branch 'upstream/master' into clean/command_and_magic

* Remove remaining unused IS_COMMAND() instances from keyboard-level config.h

This is a tentative quick fix.
I was adding the same functions for both #14426 and #14427 and they were in conflict.

* Stop using snprintf() in keymaps/five_rows/oled_display.c.

The binary size becomes 1350 bytes smaller.

make HELIX=verbose,core-oled helix/rev2/sc:five_rows
(104 bytes over) -> (95%, 1256 bytes free)

make helix/rev3_5rows:five_rows
(528 bytes over) -> (97%, 830 bytes free)

* add matrix scan rate display to OLED for keymaps/five_rows

* add matrix_output_unselect_delay.c to helix keymaps/five_rows

* add GPLv2 header

* apply review comment

* move rev3_Xrows/oled_display.c to rev3_Xrows/keymaps/default/oled_display.c

* add dummy rev3_Xrows/oled_display.c

* Add default minimum oled_task_user() to helix/rev3_Xrows/rev3_Xrows.c

* remove unnecessary comment in rev3_Xrows/keymaps/default/oled_display.c

* copy rev3_Xrows/keymaps/default/oled_display.c to rev3_Xrows/keymaps/via/oled_display.c

* Remove empty override functions, 0-9

* Remove empty override functions, A-D

* Remove empty override functions, E-H

* Remove empty override functions, handwired

* Remove empty override functions, I-L

* Remove empty override functions, M-P

* Remove empty override functions, Q-T

* Remove empty override functions, U-Z

* Change keyboard level include guards to `pragma once`

And clean up a lot of layout macros

* Oops

* Remove dangling endif

* Helix/pico use post_rules.mk insted of local_features.mk

Tested with the following procedure.
```
git checkout 77a93fec79 (qmk/develop)
make clean
make helix/pico:all:check-md5
make helix/pico/sc:all:check-md5
git checkout helix_use_post_rules.mk
make clean
make helix/pico:all:check-md5
make helix/pico/sc:all:check-md5
```

* Helix/rev2 use post_rules.mk

Tested with the following procedure.
```
git checkout 77a93fec79 (qmk/develop)
make clean
make helix/pico:all:check-md5
make helix/pico/sc:all:check-md5
make helix/rev2:all:check-md5
make helix/rev2/sc:all:check-md5
git checkout helix_use_post_rules.mk
make clean
make helix/pico:all:check-md5
make helix/pico/sc:all:check-md5
make helix/rev2:all:check-md5
make helix/rev2/sc:all:check-md5
```

* add docs

* core changes

* update keyboards to new OLED

* updated users to new OLED

* update layouts to new OLED

* fixup docs

* drashna's suggestion

* fix up docs

* new keyboards with oled

* core split changes

* remaining keyboard files

* Fix The Helix keyboards oled options

* reflect develop

Co-authored-by: Drashna Jaelre <drashna@live.com>
Co-authored-by: mtei <2170248+mtei@users.noreply.github.com>

I'm against using RGBLIGHT_ANIMATIONS because this happens.
See also #8688.

* remove keyboard-level instances of `MIDI_ENABLE = no`

Command:

```
find keyboards/ -type f -name 'rules.mk' -and -not -path '*/keymaps/*' -exec sed -i -e  '/^[ #]*MIDI_ENABLE[ \t]*=[ \t]*no/d' {} +
```

Co-Authored-By: Nick Brassel <nick@tzarc.org>

* fix case-sensitivity issues on MIDI_ENABLE

Change instances of `MIDI_ENABLE = YES` to `MIDI_ENABLE = yes`.

Command:

```
find keyboards/ -type f -name 'rules.mk' -and -not -path '*/keymaps/*' -exec sed -i -e 's;MIDI_ENABLE[ \t]*=[ \t]*[Yy][Ee][Ss];MIDI_ENABLE = yes;g' {} +
```

* replace `# MIDI controls` with `# MIDI support`

Replace `# MIDI controls` with `# MIDI support` in keyboard-level `rules.mk` files.

Command:

```
find keyboards/ -type f -name 'rules.mk' -and -not -path '*/keymaps/*' -exec sed -i -e 's;#[ \t]*MIDI[ \t]*\(controls\|support\).*;# MIDI support;g' {} +
```

* align inline comments

Aligns the inline comments to the length used by the QMK AVR rules.mk template.

Command:

```
find keyboards/ -type f -name 'rules.mk' -and -not -path '*/keymaps/*' -exec sed -i -e 's;MIDI_ENABLE *= *yes.*;MIDI_ENABLE = yes           # MIDI support;g'  {} +
```

* remove commented instances of `MIDI_ENABLE` from keyboard `rules.mk` files

Commands:

```
find keyboards/ -type f -name 'rules.mk' -and -not -path '*/keymaps/*' -exec sed -i -e 's;#\([ \t]*MIDI_ENABLE\) = yes; \1 = no ;' {} +
find keyboards/ -type f -name 'rules.mk' -and -not -path '*/keymaps/*' -exec sed -i -e 's;^\([ \t]*\)\(MIDI_ENABLE = no\);\2\1;' {} +
find keyboards/ -type f -name 'rules.mk' -and -not -path '*/keymaps/*' -exec sed -i -e '/^[ #]\+MIDI_ENABLE *= *no/d' {} +
```

* remove MIDI configuration boilerplate from keyboard config.h files

Co-authored-by: Nick Brassel <nick@tzarc.org>

* disambiguate Bootmagic rules in keymaps

The files edited by this commit were added at a point in time where `BOOTMAGIC_ENABLE = yes` enabled full Bootmagic.

This commit edits the files to specify that full Bootmagic is intended.

* remove BOOTMAGIC_ENABLE=full setting

* unify commented BOOTMAGIC_ENABLE rules in keyboards

Explicitly sets `BOOTMAGIC_ENABLE = no` in keyboards where the rule was commented out.

Command:

```
find keyboards/ -type f -name 'rules.mk' -and -not -path '*/keymaps/*' -exec sed -i -e 's;#[ \t]*\(BOOTMAGIC_ENABLE\)[ \t=]\+\([a-zA-Z]\+\).*;\1 = no       # Virtual DIP switch configuration;g' {} +
```

* remove commented Bootmagic rules from keymap/user level

Command:

```
find keyboards/ layouts/ users/ -type f -name 'rules.mk' -exec sed -i -e '/#.*\(BOOTMAGIC_ENABLE\)[ \t=]\+\([a-z]\+\).*/d' {} +
```

* update keyboard BOOTMAGIC_ENABLE rule formatting

Sets the formatting of BOOTMAGIC_ENABLE rules to `BOOTMAGIC_ENABLE = [value]`, without the inline comments (which will be replaced later).

Command:

```
find keyboards/ -type f -name 'rules.mk' -and -not -path '*/keymaps/*' -exec sed -i -e 's;\(BOOTMAGIC_ENABLE\)[ \t=]\+\([a-z]\+\).*;\1 = \2;g' '{}' +
```

* update keyboards' BOOTMAGIC_ENABLE settings

Updates keyboard `rules.mk` files to use `BOOTMAGIC_ENABLE = lite` where `BOOTMAGIC_ENABLE = full` was being used.

Command:

```
find keyboards/ -type f -name 'rules.mk' -and -not -path '*/keymaps/*' -exec sed -i -e 's;\(BOOTMAGIC_ENABLE = \)full;\1lite;g' '{}' +
```

* update keymap/user BOOTMAGIC_ENABLE settings

Updates keymap/user `rules.mk` files to use `BOOTMAGIC_ENABLE = lite` where `BOOTMAGIC_ENABLE = full` was being used.

Commands:

```
find keyboards/ -type f -name 'rules.mk' -and -path '*/keymaps/*' -exec sed -i -e 's;\(BOOTMAGIC_ENABLE[ \t=]\+\)full;\1lite;g' '{}' +
find layouts/community/ users/ -type f -name 'rules.mk' -exec sed -i -e 's;\(BOOTMAGIC_ENABLE[ \t=]\+\)full;\1lite;g' '{}' +
```

* remove and replace inline comments in keyboards and keymap/user files

Removes and replaces the inline comments, which have been updated to read `Enable Bootmagic Lite`.

Commands:

```
find keyboards/ -type f -name 'rules.mk' -and -path '*/keymaps/*' -exec sed -i -e 's;\(BOOTMAGIC_ENABLE\)[ \t=]\+\([a-z]\+\).*;\1 = \2;g' '{}' +
find layouts/community/ users/ -type f -name 'rules.mk' -exec sed -i -e 's;\(BOOTMAGIC_ENABLE\)[ \t=]\+\([a-z]\+\).*;\1 = \2;g' '{}' +
find keyboards/ layouts/community/ users/ -type f -name 'rules.mk' -exec sed -i -e 's;\(BOOTMAGIC_ENABLE = lite\);\1     # Enable Bootmagic Lite;g' '{}' +
find keyboards/ layouts/community/ users/ -type f -name 'rules.mk' -exec sed -i -e 's;\(BOOTMAGIC_ENABLE = yes\);\1      # Enable Bootmagic Lite;g' '{}' +
find keyboards/ layouts/community/ users/ -type f -name 'rules.mk' -exec sed -i -e 's;\(BOOTMAGIC_ENABLE = no\);\1       # Enable Bootmagic Lite;g' '{}' +
```

* rename improperly named makefiles

Some files intended to be used as makefiles had improper names causing them to not be used as intended when building.

This commit corrects the filenames of the affected files.

* update renamed file with new rule formatting

* update QMK's template files

Updates QMK's `rules.mk` templates to use the new inline comment.

* update QMK Docs

- remove documentation of full Bootmagic
- update links to Bootmagic Lite doc
- add doc for Magic Keycodes

* rules.mk patch for coarse/ixora and coarse/vinta

According to `helix/rev2/keymaps/fraanrosi/readme.md`, this keymap should be compiled with the following command:

```
make helix/rev2/under:fraanrosi
```

Therefore, when compiling all helix keymaps with the following command, an error occurs when compiling `fraanrosi`.

```
make helix:all
```

Therefore, add `LED_UNDERGLOW_ENABLE = yes` to `keymaps/fraanrosi/rules.mk` to suppress the error.

* Extensible split data sync capability through transactions.

- Split common transport has been split up between the transport layer
  and data layer.
- Split "transactions" model used, with convergence between I2C and
  serial data definitions.
- Slave matrix "generation count" is used to determine if the full slave
  matrix needs to be retrieved.
- Encoders get the same "generation count" treatment.
- All other blocks of data are synchronised when a change is detected.
- All transmissions have a globally-configurable deadline before a
  transmission is forced (`FORCED_SYNC_THROTTLE_MS`, default 100ms).
- Added atomicity for all core-synced data, preventing partial updates
- Added retries to AVR i2c_master's i2c_start, to minimise the number of
  failed transactions when interrupts are disabled on the slave due to
  atomicity checks.
- Some keyboards have had slight modifications made in order to ensure
  that they still build due to firmware size restrictions.

* Fixup LED_MATRIX compile.

* Parameterise ERROR_DISCONNECT_COUNT.

* Add Per Key functionality for AutoShift (#11536)

* LED Matrix: Reactive effect buffers & advanced indicators (#12588)

* [Keyboard] kint36: switch to sym_eager_pk debouncing (#12626)

* [Keyboard] kint2pp: reduce input latency by ≈10ms (#12625)

* LED Matrix: Split (#12633)

* [CI] Format code according to conventions (#12650)

* feat: infinite timeout for leader key (#6580)

* feat: implement leader_no_timeout logic

* docs(leader_key): infinite leader timeout docs

* Format code according to conventions (#12680)

* Update ADC driver for STM32F1xx, STM32F3xx, STM32F4xx (#12403)

* Fix default ADC_RESOLUTION for ADCv3 (and ADCv4)

Recent ChibiOS update removed ADC_CFGR1_RES_10BIT from the ADCv3 headers
(that macro should not have been there, because ADCv3 has CFGR instead of
CFGR1).  Fix the default value for ADC_RESOLUTION to use ADC_CFGR_RES_10BITS
if it is defined (that name is used for ADCv3 and ADCv4).

* Update ADC docs to match the actually used resolution

ADC driver for ChibiOS actually uses the 10-bit resolution by default
(probably to match AVR); fix the documentation accordingly.  Also add
both ADC_CFGR_RES_10BITS and ADC_CFGR1_RES_10BIT constants (these names
differ according to the ADC implementation in the particular MCU).

* Fix pinToMux() for B12 and B13 on STM32F3xx

Testing on STM32F303CCT6 revealed that the ADC mux values for B12 and
B13 pins were wrong.

* Add support for all possible analog pins on STM32F1xx

Added ADC mux values for pins A0...A7, B0, B1, C0...C5 on STM32F1xx
(they are the same at least for STM32F103x8 and larger F103 devices, and
also F102, F105, F107 families).  Actually tested on STM32F103C8T6
(therefore pins C0...C5 were not tested).

Pins F6...F10, which are present on STM32F103x[C-G] in 144-pin packages,
cannot be supported at the moment, because those pins are connected only
to ADC3, but the ChibiOS ADC driver for STM32F1xx supports only ADC1.

* Add support for all possible analog pins on STM32F4xx

Added ADC mux values for pins A0...A7, B0, B1, C0...C5 and optionally
F3...F10 (if STM32_ADC_USE_ADC3 is enabled).  These mux values are
apparently the same for all F4xx devices, except some smaller devices may
not have ADC3.

Actually tested on STM32F401CCU6, STM32F401CEU6, STM32F411CEU6 (using
various WeAct “Blackpill” boards); only pins A0...A7, B0, B1 were tested.

Pins F3...F10 are inside `#if STM32_ADC_USE_ADC3` because some devices
which don't have ADC3 also don't have the GPIOF port, therefore the code
which refers to Fx pins does not compile.

* Fix STM32F3xx ADC mux table in documentation

The ADC driver documentation had some errors in the mux table for STM32F3xx.
Fix this table to match the datasheet and the actual code (mux settings for
B12 and B13 were also tested on a real STM32F303CCT6 chip).

* Add STM32F1xx ADC pins to the documentation

* Add STM32F4xx ADC pins to the documentation

* Add initial support for tinyuf2 bootloader (when hosted on F411 blackpill) (#12600)

* Add support for jumping to tinyuf2 bootloader. Adds blackpill UF2 example.

* Update flashing.md

* Update chconf.h

* Update config.h

* Update halconf.h

* Update mcuconf.h

* eeprom driver: Refactor where eeprom driver initialisation (and EEPROM emulation initialisation) occurs to make it non-target-specific. (#12671)

* Add support for MCU = STM32F446 (#12619)

* Add support for MCU = STM32F446

* Update platforms/chibios/GENERIC_STM32_F446XE/configs/config.h

* Restore mcuconf.h to the one used by RT-STM32F446RE-NUCLEO64

* stm32f446: update mcuconf.h and board.h for 16MHz operation, with USB enabled, and other peripherals disabled.

* Format code according to conventions (#12682)

* Format code according to conventions (#12687)

* Add STM32L433 and L443 support (#12063)

* initial L433 commit

* change to XC

* fix L433

* disable all peripherals

* update system and peripheral clocks

* 433 change

* use its own board  files

* revert its own board files

* l433 specific change

* fix stm32l432xx define

* remove duplicate #define

* fix bootloader jump

* move to L443xx and add i2c2, spi2, usart3 to mcuconf.h

* move to L443

* move to L443

* fix sdmmc in mcuconf.h

* include STM32L443

* add L443

* Include L443 in compatible microcontrollers

* Include L443 in compatible microcontrollers

* Update config bootloader jump description

* Update ChibiOS define reasoning

* Update quantum/mcu_selection.mk

* fix git conflict

* Updated Function96 with V2 files and removed chconf.h and halconf.h (#12613)

* Fix bad PR merge for #6580. (#12721)

* Change RGB/LED Matrix to use a simple define for USB suspend (#12697)

* [CI] Format code according to conventions (#12731)

* Fixing transport's led/rgb matrix suspend state logic (#12770)

* [CI] Format code according to conventions (#12772)

* Fix comment parsing (#12750)

* Added OLED fade out support (#12086)

* fix some references to bin/qmk that slipped in (#12832)

* Resolve a number of warnings in `qmk generate-api` (#12833)

* New command: qmk console (#12828)

* stash poc

* stash

* tidy up implementation

* Tidy up slightly for review

* Tidy up slightly for review

* Bodge environment to make tests pass

* Refactor away from asyncio due to windows issues

* Filter devices

* align vid/pid printing

* Add hidapi to the installers

* start preparing for multiple hid_listeners

* udev rules for hid_listen

* refactor to move closer to end state

* very basic implementation of the threaded model

* refactor how vid/pid/index are supplied and parsed

* windows improvements

* read the report directly when usage page isn't available

* add per-device colors, the choice to show names or numbers, and refactor

* add timestamps

* Add support for showing bootloaders

* tweak the color for bootloaders

* Align bootloader disconnect with connect color

* add support for showing all bootloaders

* fix the pyusb check

* tweaks

* fix exception

* hide a stack trace behind -v

* add --no-bootloaders option

* add documentation for qmk console

* Apply suggestions from code review

* pyformat

* clean up and flesh out KNOWN_BOOTLOADERS

* Remove pointless SERIAL_LINK_ENABLE rules (#12846)

* Make Swap Hands use PROGMEM (#12284)

This converts the array that the Swap Hands feature uses to use PROGMEM,
and to read from that array, as such. Since this array never changes at
runtime, there is no reason to keep it in memory. Especially for AVR
boards, as memory is a precious resource.

* Fix another bin/qmk reference (#12856)

* [Keymap] Turn OLED off on suspend in soundmonster keymap (#10419)

* Fixup build errors on `develop` branch. (#12723)

* LED Matrix: Effects! (#12651)

* Fix syntax error when compiling for ARM (#12866)

* Remove KEYMAP and LAYOUT_kc (#12160)

* alias KEYMAP to LAYOUT

* remove KEYMAP and LAYOUT_kc

* Add setup, clone, and env to the list of commands we allow even with broken modules (#12868)

* Rename `point_t` -> `led_point_t` (#12864)

* [Keyboard] updated a vendor name / fixed minor keymap issues (#12881)

* Add missing LED Matrix suspend code to suspend.c (#12878)

* LED Matrix: Documentation (#12685)

* Deprecate `send_unicode_hex_string()` (#12602)

* Fix spelling mistake regarding LED Matrix in split_common. (#12888)

* [Keymap] Fix QWERTY/DVORAK status output for kzar keymap (#12895)

* Use milc.subcommand.config instead of qmk.cli.config (#12915)

* Use milc.subcommand.config instead

* pyformat

* remove the config test

* Add function to allow repeated blinking of one layer (#12237)

* Implement function rgblight_blink_layer_repeat to allow repeated blinking of one layer at a time

* Update doc

* Rework rgblight blinking according to requested change

* optimize storage

* Fixup housekeeping from being invoked twice per loop. (#12933)

* matrix: wait for row signal to go HIGH for every row (#12945)

I noticed this discrepancy (last row of the matrix treated differently than the
others) when optimizing the input latency of my keyboard controller, see also
https://michael.stapelberg.ch/posts/2021-05-08-keyboard-input-latency-qmk-kinesis/

Before this commit, when tuning the delays I noticed ghost key presses when
pressing the F2 key, which is on the last row of the keyboard matrix: the
dead_grave key, which is on the first row of the keyboard matrix, would be
incorrectly detected as pressed.

After this commit, all keyboard matrix rows are interpreted correctly.

I suspect that my setup is more susceptible to this nuance than others because I
use GPIO_INPUT_PIN_DELAY=0 and hence don’t have another delay that might mask
the problem.

* ensure we do not conflict with existing keymap aliases (#12976)

* Add support for up to 4 IS31FL3733 drivers (#12342)

* Convert Encoder callbacks to be boolean functions (#12805)

* [Keyboard] Fix Terrazzo build failure (#12977)

* Do not hard set config in CPTC files (#11864)

* [Keyboard] Corne - Remove legacy revision support (#12226)

* [Keymap] Update to Drashna keymap and user code (based on develop) (#12936)

* Add Full-duplex serial driver for ARM boards (#9842)

* Document LED_MATRIX_FRAMEBUFFER_EFFECTS (#12987)

* Backlight: add defines for default level and breathing state (#12560)

* Add dire message about LUFA mass storage bootloader (#13014)

* [Keyboard] Remove redundant legacy and common headers for crkbd (#13023)

Was causing compiler errors on some systems.

* Fix keyboards/keymaps for boolean encoder callback changes (#12985)

* `backlight.c`: include `eeprom.h` (#13024)

* Add changelog for 2021-05-29 Breaking Changes merge (#12939)

* Add ChangeLog for 2021-05-29 Breaking Changes Merge: initial version

* Add recent develop changes

* Sort recent develop changes

* Remove sections for ChibiOS changes per tzarc

No ChibiOS changes this round.

* Add and sort recent develop changes

* add notes about keyboard moves/deletions

* import changelog for PR 12172

Documents the change to BOOTMAGIC_ENABLE.

* update section headings

* re-sort changelog

* add additional note regarding Bootmagic changes

* remove changelog timestamp

* update dates in main Breaking Changes docs

* fix broken section anchors in previous changelogs

* add link to backlight/eeprom patch to changelog

* highlight some more changes

* link PRs from section headers

* Restore standard readme

* run: qmk cformat --core-only

Co-authored-by: James Young <18669334+noroadsleft@users.noreply.github.com>

* alias KEYMAP to LAYOUT

* remove KEYMAP and LAYOUT_kc