Menu item index followup

Marlin/src/lcd/menu/menu_filament.cpp

 void _menu_temp_filament_op(const PauseMode mode, const int8_t extruder) {
   _change_filament_mode = mode;
   _change_filament_extruder = extruder;
+  const int8_t old_index = MenuItemBase::itemIndex;
   START_MENU();
   if (LCD_HEIGHT >= 4) STATIC_ITEM_P(change_filament_header(mode), SS_DEFAULT|SS_INVERT);
   BACK_ITEM(MSG_BACK);
   #if PREHEAT_COUNT
-    const int8_t old_index = MenuItemBase::itemIndex;
     LOOP_L_N(m, PREHEAT_COUNT)
       ACTION_ITEM_N_S(m, ui.get_preheat_label(m), MSG_PREHEAT_M, _change_filament_with_preset);
-    MenuItemBase::itemIndex = old_index;
   #endif
   EDIT_ITEM_FAST_N(int3, extruder, MSG_PREHEAT_CUSTOM, &thermalManager.temp_hotend[extruder].target,
     EXTRUDE_MINTEMP, thermalManager.heater_maxtemp[extruder] - HOTEND_OVERSHOOT,
     _change_filament_with_custom
   );
   END_MENU();
+  MenuItemBase::itemIndex = old_index;
 }
 
 /**