Optimize the code a bit more, only perform calculations if they are necessary

ArduPlane/Attitude.pde

@@ -355,12 +355,14 @@ static void set_servos(void)
 		throttle_slew_limit();
 	}
 
+	// Auto flap deployment
+	if (g_rc_function[RC_Channel_aux::k_flap_auto] != NULL) {
 		if(control_mode < FLY_BY_WIRE_B) {
 			// only use radio_in if the channel is not used as flight_mode_channel
 			if (g_rc_function[RC_Channel_aux::k_flap_auto] != rc_array[g.flight_mode_channel-1]) {
-			G_RC_AUX(k_flap_auto)->radio_out = g_rc_function[RC_Channel_aux::k_flap_auto]->radio_in;
+				g_rc_function[RC_Channel_aux::k_flap_auto]->radio_out = g_rc_function[RC_Channel_aux::k_flap_auto]->radio_in;
 			} else {
-			G_RC_AUX(k_flap_auto)->radio_out = g_rc_function[RC_Channel_aux::k_flap_auto]->radio_trim;
+				g_rc_function[RC_Channel_aux::k_flap_auto]->radio_out = g_rc_function[RC_Channel_aux::k_flap_auto]->radio_trim;
 			}
 		} else if (control_mode >= FLY_BY_WIRE_B) {
 			if (control_mode == FLY_BY_WIRE_B) {
@@ -370,7 +372,6 @@ static void set_servos(void)
 			} else {
 				flapSpeedSource = g.throttle_cruise;
 			}
-        if (g_rc_function[RC_Channel_aux::k_flap_auto] != NULL) {
 			if ( flapSpeedSource > g.flap_1_speed) {
 				g_rc_function[RC_Channel_aux::k_flap_auto]->servo_out = 0;
 			} else if (flapSpeedSource > g.flap_2_speed) {
@@ -395,7 +396,7 @@ static void set_servos(void)
 	g.rc_7.output_ch(CH_7);
 	g.rc_8.output_ch(CH_8);
 #endif
- }
+}
 
 static void demo_servos(byte i) {