Previously there was a half-baked parser that looked for a fixed value in a
fixed place, but this was not robust. This approach is properly robust, in case
various different files set or override it.
This change implements the ability to get and set the WiFi back-end,
by leveraging a new script created for that purpose.
The idea is to be able to use 'wpa_supplicant' (which is the default
back-end in NetworkManager upstream) when 'iwd' (the default in
SteamOS) does not work for some reason.
This change interacts with another feature of steamos-manager, which
is to set debug mode for WiFi. Handling debug mode complicates things
substantially because those methods write config for 'iwd' and restart
the daemons/systemd units, with many interdependencies.
Instead of trying to implement all at once and attempt feature-parity
between back-ends on this aspect from the start, as a first step the
operations are just declared incompatible. As a result, if
WifiDebugMode=on the back-end cannot be changed, and conversely the
WifiDebugMode cannot be turned on when the back-end is
'wpa_supplicant'.
Co-authored-by: Manuel A. Fernandez Montecelo <mafm@igalia.com>
