ArduCopter: just call set_throttle_range()

Now set_throttle_range in AP_Motors does the right thing, calling out
the RCOutput method.

ArduCopter/radio.cpp

@@ -53,6 +53,10 @@ void Copter::init_rc_out()
     motors->init((AP_Motors::motor_frame_class)g2.frame_class.get(), (AP_Motors::motor_frame_type)g.frame_type.get());
 #if FRAME_CONFIG != HELI_FRAME
     motors->set_throttle_range(channel_throttle->get_radio_min(), channel_throttle->get_radio_max());
+#else
+    // setup correct scaling for ESCs like the UAVCAN PX4ESC which
+    // take a proportion of speed.
+    hal.rcout->set_esc_scaling(channel_throttle->get_radio_min(), channel_throttle->get_radio_max());
 #endif
 
     // delay up to 2 second for first radio input
@@ -62,10 +66,6 @@ void Copter::init_rc_out()
         read_radio();
     }
 
-    // setup correct scaling for ESCs like the UAVCAN PX4ESC which
-    // take a proportion of speed. 
-    hal.rcout->set_esc_scaling(channel_throttle->get_radio_min(), channel_throttle->get_radio_max());
-
     // check if we should enter esc calibration mode
     esc_calibration_startup_check();