Turn off DISABLE_INACTIVE_EXTRUDER with SWITCHING_NOZZLE

Fix #11183

Marlin/src/inc/Conditionals_LCD.h

 
 #define HAS_DEBUG_MENU (ENABLED(ULTIPANEL) && ENABLED(LCD_PROGRESS_BAR_TEST))
 
-// MK2 Multiplexer forces SINGLENOZZLE and kills DISABLE_INACTIVE_EXTRUDER
-#if ENABLED(MK2_MULTIPLEXER)
-  #define SINGLENOZZLE
-  #undef DISABLE_INACTIVE_EXTRUDER
-#endif
-
 /**
  * Extruders have some combination of stepper motors and hotends
  * so we separate these concepts into the defines:
  *  E_MANUAL     - Number of E steppers for LCD move options
  *
  */
-#define HOTEND_LOOP() for (int8_t e = 0; e < HOTENDS; e++)
-
 #if ENABLED(SWITCHING_EXTRUDER)                               // One stepper for every two EXTRUDERS
   #if EXTRUDERS > 4
     #define E_STEPPERS    3
   #define E_MANUAL        EXTRUDERS
 #endif
 
+// No inactive extruders with MK2_MULTIPLEXER or SWITCHING_NOZZLE
+#if ENABLED(MK2_MULTIPLEXER) || ENABLED(SWITCHING_NOZZLE)
+  #undef DISABLE_INACTIVE_EXTRUDER
+#endif
+
+// MK2 Multiplexer forces SINGLENOZZLE
+#if ENABLED(MK2_MULTIPLEXER)
+  #define SINGLENOZZLE
+#endif
+
 #if ENABLED(SINGLENOZZLE) || ENABLED(MIXING_EXTRUDER)         // One hotend, one thermistor, no XY offset
   #undef HOTENDS
   #define HOTENDS       1
   #define HOTENDS EXTRUDERS
 #endif
 
+#define HOTEND_LOOP() for (int8_t e = 0; e < HOTENDS; e++)
+
 #define DO_SWITCH_EXTRUDER (ENABLED(SWITCHING_EXTRUDER) && (DISABLED(SWITCHING_NOZZLE) || SWITCHING_EXTRUDER_SERVO_NR != SWITCHING_NOZZLE_SERVO_NR))
 
 /**