Plane: pass height to landing gear update

ArduPlane/ArduPlane.cpp

@@ -102,7 +102,7 @@ const AP_Scheduler::Task Plane::scheduler_tasks[] = {
     SCHED_TASK(publish_osd_info, 1, 10),
 #endif
 #if LANDING_GEAR_ENABLED == ENABLED
-    SCHED_TASK_CLASS(AP_LandingGear, &plane.g2.landing_gear, update, 10, 50),
+    SCHED_TASK(landing_gear_update, 5, 50),
 #endif
 };
 

ArduPlane/Plane.h

@@ -961,6 +961,7 @@ private:
     void takeoff_calc_pitch(void);
     int8_t takeoff_tail_hold(void);
     int16_t get_takeoff_pitch_min_cd(void);
+    void landing_gear_update(void);
     void complete_auto_takeoff(void);
     void ahrs_update();
     void update_speed_height(void);

ArduPlane/takeoff.cpp

@@ -272,3 +272,14 @@ void Plane::complete_auto_takeoff(void)
     }
 #endif
 }
+
+
+#if LANDING_GEAR_ENABLED == ENABLED
+/*
+  update landing gear
+ */
+void Plane::landing_gear_update(void)
+{
+    g2.landing_gear.update(relative_ground_altitude(g.rangefinder_landing));
+}
+#endif