Copter: remove unused ap.gps_status flag

ArduCopter/AP_State.pde

@@ -127,13 +127,3 @@ void set_compass_healthy(bool b)
     }
     ap.compass_status = b;
 }
-
-void set_gps_healthy(bool b)
-{
-    if(ap.gps_status != b){
-        if(false == b){
-            Log_Write_Event(DATA_LOST_GPS);
-        }
-    }
-    ap.gps_status = b;
-}

ArduCopter/ArduCopter.pde

@@ -1337,8 +1337,6 @@ static void update_GPS(void)
     g_gps->update();
     update_GPS_light();
 
-    set_gps_healthy(g_gps->status() >= GPS::GPS_OK_FIX_3D);
-
     if (g_gps->new_data && last_gps_time != g_gps->time && g_gps->status() >= GPS::GPS_OK_FIX_2D) {
         // clear new data flag
         g_gps->new_data = false;