OBS Virtual Camera support on Linux

[Avasam]

Is your feature request related to a problem? Please describe.

My c920 webcam simply won't work (may or may not be a vmware issue).
I can't get the virtual cam working in OBS.
So I can't test or implement this feature myself 😕 (for all I know it's already working as-is).

Describe the solution you'd like

It should be possible to use OBS Virtual camera with AutoSplit on Linux.
Webcam/Capture device support optional.

Additional context

Extracted from #224

v4l2loopback Video Devices don't work atm Avasam#55

[Avasam]

From @Yanis002 on Discord:

I was curious about the OBS virtual camera on linux, so I tried it and it seems to work for me, same with using my capture card
[...]
it seems I got lucky, I tried to do it again but now it seems I get the same behavior as you did, except the virtual camera isn't listed at all, my obs setup changed since last time though, previously I was using the flatpak one but I switched to the PPA recently, that could explain it? 🤔