Set filament runout pins.

Author: knutwurst

Marlin/src/pins/ramps/pins_RAMPS.h

@@ -280,6 +280,13 @@
   #endif
 #endif
 
+
+#if ANY(KNUTWURST_CHIRON, KNUTWURST_4MAXP2)
+  #define FIL_RUNOUT_PIN 33
+#else
+  #define FIL_RUNOUT_PIN 19
+#endif
+
 #ifndef PS_ON_PIN
   #define PS_ON_PIN                           12
 #endif