Move M42 to cpp

Marlin/src/Marlin.cpp

 /**
  * Sensitive pin test for M42, M226
  */
-static bool pin_is_protected(const int8_t pin) {
+bool pin_is_protected(const int8_t pin) {
   static const int8_t sensitive_pins[] PROGMEM = SENSITIVE_PINS;
   for (uint8_t i = 0; i < COUNT(sensitive_pins); i++)
     if (pin == (int8_t)pgm_read_byte(&sensitive_pins[i])) return true;
   return false;
 }
 
-#include "gcode/control/M42.h"
-
 #if ENABLED(PINS_DEBUGGING)
   #include "gcode/config/M43.h"
 #endif

Marlin/src/Marlin.h

 
 void calculate_volumetric_multipliers();
 
+bool pin_is_protected(const int8_t pin);
+
 #endif // __MARLIN_H__

Marlin/src/gcode/control/M42.h → Marlin/src/gcode/control/M42.cpp

  *
  */
 
+#include "../gcode.h"
+#include "../../Marlin.h" // for pin_is_protected
+#include "../../inc/MarlinConfig.h"
+
 /**
  * M42: Change pin status via GCode
  *
  *  P<pin>  Pin number (LED if omitted)
  *  S<byte> Pin status from 0 - 255
  */
-void gcode_M42() {
+void GcodeSuite::M42() {
   if (!parser.seenval('S')) return;
   const byte pin_status = parser.value_byte();
 

Marlin/src/gcode/gcode.cpp

 // Placeholders for non-migrated codes
 //
 extern void gcode_M18_M84();
-extern void gcode_M42();
 extern void gcode_M43();
 extern void gcode_M48();
 extern void gcode_M75();
 
       case 31: M31(); break;      // M31: Report time since the start of SD print or last M109
 
-      case 42: // M42: Change pin state
-        gcode_M42(); break;
+      case 42: M42(); break;      // M42: Change pin state
 
       #if ENABLED(PINS_DEBUGGING)
         case 43: // M43: Read pin state