Bug#1001756: nvidia-legacy-340xx-driver: udev rules broken/stale; no graphical login

[Oswald Buddenhagen]

Package: nvidia-legacy-340xx-driver
Version: 340.108-11
Severity: important

udev fails to associate the nvidia graphics card with a seat (query with
`loginctl seat-status seat0`), which results in modern display managers
like sddm not even attempting to start a graphical login screen.

special rules are needed, as the usual drm udev rules don't work due to
the legacy driver not providing a drm interface (it appears that the 390
driver is the first one to do so).

adding /etc/udev/rules.d/61-nvidia.rules with the following content
fixes it:

SUBSYSTEM=="pci", ATTRS{vendor}=="0x10de", DRIVERS=="nvidia", TAG+="seat", TAG+="master-of-seat"

(that file should obviously to go to /lib/udev/rules.d in the package.)