Linux 5.4 rc2

Back to the usual Sunday afternoon schedule, and -rc2 is out.

Nothing particularly stands out here. It's roughly one third arch
updates, one third drivers, and one third "misc" (kvm selftests,
networking, filesystems, core kernel, header files etc). No real
theme, just random fixes all over the place.

The diffstat is pretty flat too, which is just another sign of "small
fixes all over".

So nothing looks particularly worrisome, but usually rc2 is fairly
calm and it takes a while for any regressions to be noticed. And this
one was one of the nice small rc2's (5.2 and 5.3 rc2's were both
larger than usual), but maybe it's because it was also a day shorter.

Anyway, nothing for it but to go out and test, people. Go at it!