wait_tempbed has to be called only if there is a tempbed!

MK/module/MK_Main.cpp

@@ -3117,7 +3117,8 @@ inline void wait_heater(bool no_wait_for_cooling = true) {
   KEEPALIVE_STATE(IN_HANDLER);
 }
 
-inline void wait_bed(bool no_wait_for_cooling = true) {
+#if HAS(TEMP_BED)
+  inline void wait_bed(bool no_wait_for_cooling = true) {
 
     #if TEMP_BED_RESIDENCY_TIME > 0
       millis_t residency_start_ms = 0;
@@ -3187,7 +3188,8 @@ inline void wait_bed(bool no_wait_for_cooling = true) {
     } while (!cancel_heatup && TEMP_BED_CONDITIONS);
     LCD_MESSAGEPGM(MSG_BED_DONE);
     KEEPALIVE_STATE(IN_HANDLER);
-}
+  }
+#endif // HAS(TEMP_BED)
 
 #if HAS(TEMP_CHAMBER)
   inline void wait_chamber(bool no_wait_for_heating = true) {
@@ -7882,8 +7884,10 @@ inline void gcode_M503() {
         setTargetHotend(old_target_temperature[e], e);
         wait_heater();
       }
+      #if HAS(TEMP_BED)
         setTargetBed(old_target_temperature_bed);
         wait_bed();
+      #endif
     }
 
     // Show load message