ACM : temp fix for throttle output limit

I had a bad crash when I lost authority. The logs showed the throttle pegged at 1000 which killed my control. We went round and round on this and somehow settled on no limit. That wasn't a good idea. This should really be hard coded into the Motors Library, but for now I'm just sticking it here.

ArduCopter/motors.pde

@@ -192,6 +192,9 @@ static void init_disarm_motors()
 static void
 set_servos_4()
 {
+	// temp fix for bad attitude
+	g.rc_3.servo_out = min(g.rc_3.servo_out, 800);
+
 	motors.output();
 }