[review] Support for abortable operations that wait to be aborted

[Aleksander Morgado]

Hey,

The following MR is ready for review:
https://gitlab.freedesktop.org/mobile-broadband/libqmi/merge_requests/50

The abortable operations supported by libqmi (NAS Network Scan and WDS
Start Network) were not waiting for the command abortion to complete
before returning an error, and so, if the response to the operation
was received just before the abort request was processed by the
device, we would end up with a device that reported a successful
result while we assumed the command was actually aborted. This was
causing logic errors in WDS Start Network especially, as the client
would get reported a failed attempt to start network while the attempt
was actually successful.

Fix this, by making these abortable operations wait for the abortion
to complete, and if any good response is received before the abortion
happens, we would keep the good response instead and cancel the abort
request.

This MR in libqmi would solve the issues seen in the ModemManager MR
https://gitlab.freedesktop.org/mobile-broadband/ModemManager/merge_requests/100.
I believe that once the libqmi fixes are in place, the remaining
commits in that MM MR would no longer be required.

-- 
Aleksander
https://aleksander.es