[Patch]Unref GIOChannel in g_at_chat_new_from_tty

[Marcel Holtmann]

Hi Zhenhua,

> Attached is the patch to unref GIOChannel in g_at_chat_new_from_tty. If the 
> GAtChat is created from g_at_chat_new, the reference count of channel is 
> increased by g_io_add_watch_full(channel), so we need to unref it.
> 
> If GAtChat is failed to create, we also need to unref channel to free it.

patch has been applied. Thanks.

Regards

Marcel