Move M401_M402 to cpp

Marlin/src/Marlin.cpp

   return false;
 }
 
-#if HAS_BED_PROBE
-  #include "gcode/probe/M401_M402.h"
-#endif
-
 void quickstop_stepper() {
   stepper.quick_stop();
   stepper.synchronize();

Marlin/src/gcode/gcode.cpp

 extern void gcode_M350();
 extern void gcode_M351();
 extern void gcode_M355();
-extern void gcode_M401();
-extern void gcode_M402();
 extern void gcode_M428();
 extern void gcode_M500();
 extern void gcode_M501();
       case 400: M400(); break;    // M400: Finish all moves
 
       #if HAS_BED_PROBE
-        case 401: // M401: Deploy probe
-          gcode_M401();
-          break;
-        case 402: // M402: Stow probe
-          gcode_M402();
-          break;
-      #endif // HAS_BED_PROBE
+        case 401: M401(); break;  // M401: Deploy probe
+        case 402: M402(); break;  // M402: Stow probe
+      #endif
 
       #if ENABLED(FILAMENT_WIDTH_SENSOR)
         case 404:  // M404: Enter the nominal filament width (3mm, 1.75mm ) N<3.0> or display nominal filament width

Marlin/src/gcode/probe/M401_M402.h → Marlin/src/gcode/probe/M401_M402.cpp

  *
  */
 
+#include "../../inc/MarlinConfig.h"
+
+#if HAS_BED_PROBE
+
+#include "../gcode.h"
+#include "../../module/probe.h"
+
 /**
  * M401: Engage Z Servo endstop if available
  */
-void gcode_M401() { DEPLOY_PROBE(); }
+void GcodeSuite::M401() { DEPLOY_PROBE(); }
 
 /**
  * M402: Retract Z Servo endstop if enabled
  */
-void gcode_M402() { STOW_PROBE(); }
+void GcodeSuite::M402() { STOW_PROBE(); }
 
+#endif // HAS_BED_PROBE