1. int _stdcall unregister_camera_event(int camera, CAMERA_EVENT event, int event_id);
2. int _stdcall unregister_client_event(void* client, CLIENT_EVENT event, int event_id);
3. int _stdcall unregister_global_event(GLOBAL_EVENT event, int event_id);
camera:[in]，The camera's handle which is form new_camera
client:[in]，The client's object which is from new_client
event:[in]，The event which want to unregister
event_id:[in]，The event id to unregister which is from register_event set
Return ERROR_OK if success，else refer to the definition of error number
Unregister the event which is registered before.