GATTS_CreateService() function

* Function GATTS_CreateService * Description This function is called to reserve a block of handles for a service. * *** It should be called only once per service instance *** * Parameter gatt_if : application if * p_svc_uuid : service UUID * svc_inst : instance of the service inside the application * num_handles : number of handles needed by the service. * is_pri : is a primary service or not. * Returns service handle if successful, otherwise 0.