Correct bug in initialization of auxiliary channels

The value of aux_servo_function[CH_x] was not being set before the radio init_rc_in() function was setting channel angle/range.

ArduPlane/radio.pde

@@ -23,6 +23,7 @@ static void init_rc_in()
 	g.channel_throttle.dead_zone = 6;
 
 	//set auxiliary ranges
+	update_aux_servo_function(&g.rc_5, &g.rc_6, &g.rc_7, &g.rc_8);
 	G_RC_AUX(k_flap)->set_range(0,100);
 	G_RC_AUX(k_flap_auto)->set_range(0,100);
 	G_RC_AUX(k_aileron)->set_angle(SERVO_MAX);