Sanity check PIDTEMPBED plus BED_LIMIT_SWITCHING

Marlin/SanityCheck.h

 #endif
 
 /**
- * Mesh Bed Leveling
+ * Bed Heating Options - PID vs Limit Switching
  */
+#if ENABLED(PIDTEMPBED) && ENABLED(BED_LIMIT_SWITCHING)
+  #error To use BED_LIMIT_SWITCHING you must disable PIDTEMPBED.
+#endif
 
+/**
+ * Mesh Bed Leveling
+ */
 #if ENABLED(MESH_BED_LEVELING)
   #if ENABLED(DELTA)
     #error MESH_BED_LEVELING does not yet support DELTA printers.

Marlin/example_configurations/SCARA/Configuration.h

 // If this is enabled, find your own PID constants below.
 #define PIDTEMPBED
 
-#define BED_LIMIT_SWITCHING
+//#define BED_LIMIT_SWITCHING
 
 // This sets the max power delivered to the bed, and replaces the HEATER_BED_DUTY_CYCLE_DIVIDER option.
 // all forms of bed control obey this (PID, bang-bang, bang-bang with hysteresis)

Marlin/temperature.cpp

         soft_pwm_bed = 0;
         WRITE_HEATER_BED(LOW);
       }
-    #else // BED_LIMIT_SWITCHING
+    #else // !PIDTEMPBED && !BED_LIMIT_SWITCHING
       // Check if temperature is within the correct range
       if (current_temperature_bed > BED_MINTEMP && current_temperature_bed < BED_MAXTEMP) {
         soft_pwm_bed = current_temperature_bed < target_temperature_bed ? MAX_BED_POWER >> 1 : 0;