Move G2_G3 to cpp

Marlin/src/gcode/gcode.cpp

 //
 // Placeholders for non-migrated codes
 //
-extern void gcode_G2_G3(bool clockwise);
 extern void gcode_G4();
 extern void gcode_G5();
 extern void gcode_G12();
       #if ENABLED(ARC_SUPPORT) && DISABLED(SCARA)
         case 2: // G2: CW ARC
         case 3: // G3: CCW ARC
-          gcode_G2_G3(parser.codenum == 2);
+          G2_G3(parser.codenum == 2);
           break;
       #endif
 

Marlin/src/gcode/gcode.h

   );
 
   #if ENABLED(ARC_SUPPORT)
-    static void G2_G3(bool clockwise);
+    static void G2_G3(const bool clockwise);
   #endif
 
   static void G4();

Marlin/src/gcode/motion/G2_G3.h → Marlin/src/gcode/motion/G2_G3.cpp

  *
  */
 
+#include "../../inc/MarlinConfig.h"
+
+#if ENABLED(ARC_SUPPORT)
+
 #include "../gcode.h"
+#include "../../module/motion.h"
+#include "../../module/planner.h"
+#include "../../module/temperature.h"
 
 #if N_ARC_CORRECTION < 1
   #undef N_ARC_CORRECTION
  *    G2 I10           ; CW circle centered at X+10
  *    G3 X20 Y12 R14   ; CCW circle with r=14 ending at X20 Y12
  */
-void gcode_G2_G3(bool clockwise) {
+void GcodeSuite::G2_G3(const bool clockwise) {
   if (IsRunning()) {
 
     #if ENABLED(SF_ARC_FIX)
       relative_mode = true;
     #endif
 
-    gcode.get_destination_from_command();
+    get_destination_from_command();
 
     #if ENABLED(SF_ARC_FIX)
       relative_mode = relative_mode_backup;
 
       // Send the arc to the planner
       plan_arc(destination, arc_offset, clockwise);
-      gcode.refresh_cmd_timeout();
+      refresh_cmd_timeout();
     }
     else {
       // Bad arguments
     }
   }
 }
+
+#endif // ARC_SUPPORT