Rework landing gear logic

- remove deprecated actuator_controls[INDEX_LANDING_GEAR]
- remove dead code in mc rate controller that used to prevent it from being retracted
on the ground (anyway had no effect as it only affected the actuator_control[LANDING_GEAR]
which wasn't sent to the control allocation)
- for VTOLs handle deployment/retraction of landing gear in AUTO  as a MC (retract if
more than 2m above ground, deploy if WP is a landing WP), plus additionally when transition
flight task is called (ALTITUDE mode and higher)
- for FW in AUTO: add logic in FW Position Controller, depending on waypoint type mainly
- manual landing gear settings always come through (a manual command overrides a previous
auto command, and vice-versa)

Signed-off-by: Silvan Fuhrer <silvan@auterion.com>

src/modules/vtol_att_control/tiltrotor.cpp

@@ -42,8 +42,6 @@
 #include "tiltrotor.h"
 #include "vtol_att_control_main.h"
 
-#include <uORB/topics/landing_gear.h>
-
 using namespace matrix;
 using namespace time_literals;
 
@@ -450,14 +448,6 @@ void Tiltrotor::fill_actuator_outputs()
 		collective_thrust_normalized_setpoint = mc_in[actuator_controls_s::INDEX_THROTTLE] * _mc_throttle_weight;
 	}
 
-	// Landing gear
-	if (_vtol_mode == vtol_mode::MC_MODE) {
-		mc_out[actuator_controls_s::INDEX_LANDING_GEAR] = landing_gear_s::GEAR_DOWN;
-
-	} else {
-		mc_out[actuator_controls_s::INDEX_LANDING_GEAR] = landing_gear_s::GEAR_UP;
-	}
-
 	// Fixed wing output
 	if (_param_vt_elev_mc_lock.get()  && _vtol_mode == vtol_mode::MC_MODE) {
 		fw_out[actuator_controls_s::INDEX_ROLL]  = 0;