[review] Voice implementation fixes

[Aleksander Morgado]

Hey,

I've pushed a branch to gitlab for review:
https://gitlab.freedesktop.org/mobile-broadband/ModemManager/merge_requests/2

It includes several fixed and improvements in the voice API
implementation for generic and huawei modems. I've been able to
validate and test all APIs successfully now with a u-blox TOBY-L4.

Comments?

-- 
Aleksander
https://aleksander.es