Plane: don't do throttle ESC scaling for quadplanes

ArduPlane/radio.cpp

@@ -38,10 +38,13 @@ void Plane::set_control_channels(void)
         SRV_Channels::set_safety_limit(SRV_Channel::k_throttle, aparm.throttle_min<0?SRV_Channel::SRV_CHANNEL_LIMIT_TRIM:SRV_Channel::SRV_CHANNEL_LIMIT_MIN);
     }
 
+    if (!quadplane.enable) {
         // setup correct scaling for ESCs like the UAVCAN PX4ESC which
-    // take a proportion of speed
+        // take a proportion of speed. For quadplanes we use AP_Motors
+        // scaling
         g2.servo_channels.set_esc_scaling_for(SRV_Channel::k_throttle);
     }
+}
 
 /*
   initialise RC input channels