rp2040: *_PAL_MODE overridable for this platform too (#20314)

Co-authored-by: Sergey Vlasov <sigprof@gmail.com>

platforms/chibios/chibios_config.h

@@ -33,26 +33,40 @@
 #    define RP2040_PWM_CHANNEL_A 1U
 #    define RP2040_PWM_CHANNEL_B 2U
 
-#    define BACKLIGHT_PAL_MODE (PAL_MODE_ALTERNATE_PWM | PAL_RP_PAD_DRIVE12 | PAL_RP_GPIO_OE)
+#    ifndef BACKLIGHT_PAL_MODE
+#        define BACKLIGHT_PAL_MODE (PAL_MODE_ALTERNATE_PWM | PAL_RP_PAD_DRIVE12 | PAL_RP_GPIO_OE)
+#    endif
 #    define BACKLIGHT_PWM_COUNTER_FREQUENCY 1000000
 #    define BACKLIGHT_PWM_PERIOD BACKLIGHT_PWM_COUNTER_FREQUENCY / 2048
 
-#    define AUDIO_PWM_PAL_MODE (PAL_MODE_ALTERNATE_PWM | PAL_RP_PAD_DRIVE12 | PAL_RP_GPIO_OE)
+#    ifndef AUDIO_PWM_PAL_MODE
+#        define AUDIO_PWM_PAL_MODE (PAL_MODE_ALTERNATE_PWM | PAL_RP_PAD_DRIVE12 | PAL_RP_GPIO_OE)
+#    endif
 #    define AUDIO_PWM_COUNTER_FREQUENCY 500000
 
 #    define usb_lld_endpoint_fields
 
-#    define I2C1_SCL_PAL_MODE (PAL_MODE_ALTERNATE_I2C | PAL_RP_PAD_SLEWFAST | PAL_RP_PAD_PUE | PAL_RP_PAD_DRIVE4)
-#    define I2C1_SDA_PAL_MODE I2C1_SCL_PAL_MODE
+#    ifndef I2C1_SCL_PAL_MODE
+#        define I2C1_SCL_PAL_MODE (PAL_MODE_ALTERNATE_I2C | PAL_RP_PAD_SLEWFAST | PAL_RP_PAD_PUE | PAL_RP_PAD_DRIVE4)
+#    endif
+#    ifndef I2C1_SDA_PAL_MODE
+#        define I2C1_SDA_PAL_MODE (PAL_MODE_ALTERNATE_I2C | PAL_RP_PAD_SLEWFAST | PAL_RP_PAD_PUE | PAL_RP_PAD_DRIVE4)
+#    endif
 
 #    define USE_I2CV1_CONTRIB
 #    if !defined(I2C1_CLOCK_SPEED)
 #        define I2C1_CLOCK_SPEED 400000
 #    endif
 
-#    define SPI_SCK_PAL_MODE (PAL_MODE_ALTERNATE_SPI | PAL_RP_PAD_SLEWFAST | PAL_RP_PAD_DRIVE4)
-#    define SPI_MOSI_PAL_MODE SPI_SCK_PAL_MODE
-#    define SPI_MISO_PAL_MODE SPI_SCK_PAL_MODE
+#    ifndef SPI_SCK_PAL_MODE
+#        define SPI_SCK_PAL_MODE (PAL_MODE_ALTERNATE_SPI | PAL_RP_PAD_SLEWFAST | PAL_RP_PAD_DRIVE4)
+#    endif
+#    ifndef SPI_MOSI_PAL_MODE
+#        define SPI_MOSI_PAL_MODE (PAL_MODE_ALTERNATE_SPI | PAL_RP_PAD_SLEWFAST | PAL_RP_PAD_DRIVE4)
+#    endif
+#    ifndef SPI_MISO_PAL_MODE
+#        define SPI_MISO_PAL_MODE (PAL_MODE_ALTERNATE_SPI | PAL_RP_PAD_SLEWFAST | PAL_RP_PAD_DRIVE4)
+#    endif
 #endif
 
 // STM32 compatibility