Navigator: remove deprecated _can_loiter_at_sp and _need_takeoff

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

src/modules/navigator/mission.h

@@ -133,11 +133,6 @@ private:
 	 */
 	void set_mission_items();
 
-	/**
-	 * Returns true if we need to do a takeoff at the current state
-	 */
-	bool do_need_vertical_takeoff();
-
 	/**
 	 * Returns true if we need to move to waypoint location before starting descent
 	 */
@@ -348,8 +343,6 @@ private:
 
 	float _mission_init_climb_altitude_amsl{NAN};	/**< altitude AMSL the vehicle will climb to when mission starts */
 
-	bool _need_takeoff{true};					/**< if true, then takeoff must be performed before going to the first waypoint (if needed) */
-
 	enum {
 		MISSION_TYPE_NONE,
 		MISSION_TYPE_MISSION