Add servos to pins_FYSTEC_F6_13.h

Marlin/src/pins/pins_FYSETC_F6_13.h

 #endif
 
 //
+// Servos
+//
+#define SERVO0_PIN         13
+#define SERVO1_PIN         11    // (PS_ON_PIN)
+#define SERVO2_PIN         10    // (FIL_RUNOUT_PIN)
+#define SERVO3_PIN          4    // (RGB_LED_G_PIN)
+
+//
 // Limit Switches
 //
 #define X_MIN_PIN          63
 #define Z_MAX_PIN           9
 
 #ifndef FIL_RUNOUT_PIN
-  #define FIL_RUNOUT_PIN   10
+  #define FIL_RUNOUT_PIN   SERVO2_PIN
 #endif
 
 //
 #define KILL_PIN           41
 
 #ifndef PS_ON_PIN
-  #define PS_ON_PIN        11   // Servos pin
+  #define PS_ON_PIN        SERVO1_PIN
 #endif
 
 #ifndef RGB_LED_R_PIN
   #define RGB_LED_R_PIN     3
 #endif
 #ifndef RGB_LED_G_PIN
-  #define RGB_LED_G_PIN     4
+  #define RGB_LED_G_PIN    SERVO3_PIN
 #endif
 #ifndef RGB_LED_B_PIN
   #define RGB_LED_B_PIN     9