RC_Channel_Aux: Add new landing gear control to Aux_servo_function_t enum.

Conflicts:
	libraries/RC_Channel/RC_Channel_aux.h

libraries/RC_Channel/RC_Channel_aux.h

@@ -68,6 +68,7 @@ public:
         k_steering              = 26,            ///< ground steering, used to separate from rudder
         k_parachute_release     = 27,            ///< parachute release
         k_epm                   = 28,            ///< epm gripper
+        k_landing_gear_control  = 29,            ///< landing gear controller
         k_nr_aux_servo_functions         ///< This must be the last enum value (only add new values _before_ this one)
     } Aux_servo_function_t;