Reduce buffer size of EspSoftwareSerial instances

code/espurna/sensors/MHZ19Sensor.h

@@ -76,7 +76,7 @@ class MHZ19Sensor : public BaseSensor {
 
             if (_serial) delete _serial;
 
-            _serial = new SoftwareSerial(_pin_rx, _pin_tx, false, 256);
+            _serial = new SoftwareSerial(_pin_rx, _pin_tx, false, 32);
             _serial->begin(9600);
             calibrateAuto(false);
 

code/espurna/sensors/PMSX003Sensor.h

@@ -67,7 +67,7 @@ class PMSX003Sensor : public BaseSensor {
             if (_serial) delete _serial;
             if (_pms) delete _pms;
 
-            _serial = new SoftwareSerial(_pin_rx, _pin_tx, false, 256);
+            _serial = new SoftwareSerial(_pin_rx, _pin_tx, false, 32);
             _serial->begin(9600);
             _pms = new PMS(* _serial);
             _pms->passiveMode();

code/espurna/sensors/V9261FSensor.h

@@ -65,7 +65,7 @@ class V9261FSensor : public BaseSensor {
 
             if (_serial) delete _serial;
 
-            _serial = new SoftwareSerial(_pin_rx, SW_SERIAL_UNUSED_PIN, _inverted, 256);
+            _serial = new SoftwareSerial(_pin_rx, SW_SERIAL_UNUSED_PIN, _inverted, 32);
             _serial->begin(V9261F_BAUDRATE);
 
         }