Plane: remove annoying ice_update shim

ArduPlane/ArduPlane.cpp

@@ -57,7 +57,7 @@ const AP_Scheduler::Task Plane::scheduler_tasks[] = {
     SCHED_TASK_CLASS(AP_Baro, &plane.barometer, accumulate, 50, 150),
     SCHED_TASK(update_notify,          50,    300),
     SCHED_TASK(read_rangefinder,       50,    100),
-    SCHED_TASK(ice_update,             10,    100),
+    SCHED_TASK_CLASS(AP_ICEngine, &plane.g2.ice_control, update, 10, 100),
     SCHED_TASK(compass_cal_update,     50,    50),
     SCHED_TASK(accel_cal_update,       10,    50),
 #if OPTFLOW == ENABLED

ArduPlane/Plane.h

@@ -915,7 +915,6 @@ private:
     void read_rangefinder(void);
     void read_airspeed(void);
     void rpm_update(void);
-    void ice_update(void);
     void init_ardupilot();
     void startup_ground(void);
     enum FlightMode get_previous_mode();

ArduPlane/sensors.cpp

@@ -104,13 +104,6 @@ void Plane::rpm_update(void)
     }
 }
 
-/*
-  update AP_ICEngine
- */
-void Plane::ice_update(void)
-{
-    g2.ice_control.update();
-}
 // update error mask of sensors and subsystems. The mask
 // uses the MAV_SYS_STATUS_* values from mavlink. If a bit is set
 // then it indicates that the sensor or subsystem is present but