Add a dependency for z servo macros

Marlin/Marlin_main.cpp

@@ -493,8 +493,10 @@ static bool send_ok[BUFSIZE];
 #if HAS_SERVOS
   Servo servo[NUM_SERVOS];
   #define MOVE_SERVO(I, P) servo[I].move(P)
-  #define DEPLOY_Z_SERVO() MOVE_SERVO(Z_ENDSTOP_SERVO_NR, z_servo_angle[0])
-  #define STOW_Z_SERVO() MOVE_SERVO(Z_ENDSTOP_SERVO_NR, z_servo_angle[1])
+  #if HAS_Z_SERVO_ENDSTOP
+    #define DEPLOY_Z_SERVO() MOVE_SERVO(Z_ENDSTOP_SERVO_NR, z_servo_angle[0])
+    #define STOW_Z_SERVO() MOVE_SERVO(Z_ENDSTOP_SERVO_NR, z_servo_angle[1])
+  #endif
 #endif
 
 #ifdef CHDK