Fix missing pull-down on OBS Pro and remove double button pin initialization

Author: FabianSchwartau

src/OpenBikeSensorFirmware.cpp

@@ -237,7 +237,6 @@ void setup() {
   // Configure button pin as INPUT
   //##############################################################
 
-  pinMode(PUSHBUTTON_PIN, INPUT);
   pinMode(IP5306_BUTTON, OUTPUT);
   digitalWrite(IP5306_BUTTON, LOW);
   pinMode(BatterieVoltage_PIN, INPUT);

src/utils/button.cpp

@@ -26,7 +26,7 @@
 #include "variant.h"
 
 Button::Button(int pin) : mPin(pin) {
-  pinMode(pin, INPUT);
+  pinMode(pin, INPUT_PULLDOWN);
   mLastStateChangeMillis = mLastRawReadMillis = millis();
   mLastState = mLastRawState = read();
 }