Move M82_M83 to cpp

Marlin/src/Marlin.cpp

   return false;
 }
 
-#include "gcode/units/M82_M83.h"
-
 #include "gcode/control/M18_M84.h"
 
 #include "gcode/control/M85.h"

Marlin/src/gcode/gcode.cpp

 // Placeholders for non-migrated codes
 //
 extern void gcode_M18_M84();
-extern void gcode_M82();
-extern void gcode_M83();
 extern void gcode_M85();
 extern void gcode_M92();
 extern void gcode_M100();
 
       case 81: M81(); break;      // M81: Turn off Power, including Power Supply, if possible
 
-      case 82: // M82: Set E axis normal mode (same as other axes)
-        gcode_M82();
-        break;
-      case 83: // M83: Set E axis relative mode
-        gcode_M83();
-        break;
+      case 82: M82(); break;      // M82: Set E axis normal mode (same as other axes)
+      case 83: M83(); break;      // M83: Set E axis relative mode
+
       case 18: // M18 => M84
       case 84: // M84: Disable all steppers or set timeout
         gcode_M18_M84();

Marlin/src/gcode/units/M82_M83.h → Marlin/src/gcode/units/M82_M83.cpp

  *
  */
 
+#include "../gcode.h"
+
 /**
  * M82: Set E codes absolute (default)
  */
-void gcode_M82() { gcode.axis_relative_modes[E_AXIS] = false; }
+void GcodeSuite::M82() { axis_relative_modes[E_AXIS] = false; }
 
 /**
  * M83: Set E codes relative while in Absolute Coordinates (G90) mode
  */
-void gcode_M83() { gcode.axis_relative_modes[E_AXIS] = true; }
+void GcodeSuite::M83() { axis_relative_modes[E_AXIS] = true; }