If we couldn't find the name on the bus or the ratbagd process already
terminated, return None and fail.
Signed-off-by: Peter Hutterer <peter.hutterer@who-t.net>
We want to share as much as possible between ratbagctl.devel and
ratbagctl.test, so better have a separate file that knows how to
properly spawn the dbus daemon and terminate it.
Signed-off-by: Benjamin Tissoires <benjamin.tissoires@gmail.com>