Process an internal log message.

def handle_log_message(msg):  # pylint: disable=useless-return
    """Process an internal log message."""
    msg.gateway.can_log = True
    _LOGGER.debug(
        'n:%s c:%s t:%s s:%s p:%s', msg.node_id, msg.child_id, msg.type,
        msg.sub_type, msg.payload)
    return None