Async notifier for the channel close process, with support for a user defined data.
Function using this handler:
This handler allows you to defined a notify function that will be called once the channel close indication is received. This is mainly used by vortex_channel_close to avoid caller get blocked by calling that function.
Data received is the channel num this notification applies to, the channel closing status and if was_closed is axl_false (the channel was not closed) code hold error code returned and msg the message returned by remote peer.