Fix SELinux

[samcday]

SELinux is decidedly broken in OCI images booted with bootc or rpm-ostree.

For now I'm going to just disable it entirely, since keeping it happy by working around the labelling issues is a Sisyphean task. I've already run into both the examples listed in the linked issue: swtpm and greetd problems.

My understanding is that rechunk (#1) should fix this, but I haven't managed to get that working yet.

[samcday]

Sadly, rechunk seems to have made things significantly worse. I just tried booting the first image processed with rechunk + SELinux enabled. Things were so broken that agetty couldn't spawn on a VT. Trying to SSH in yielded "A valid context for sam could not be obtained.".

I think I'm sadly coming to the same conclusion here as I have with CoreOS: defense in depth would be great but having a computer that actually works is more important. SELinux is just so not worth the trouble.