This adds compatibility with newer kernels, which fixes
nixosTests.zfs.series_2_1, which broke when the default kernel version
was bumped.
This means we no longer need the removeLinuxDRM option at all, but
I've kept it around as a no-op so people can leave it set in case the
same thing happens again in future.
This re-introduces the old stable ZFS version we had in the past following
the many predicted issues of ZFS 2.2.x series, that is much more stable
than any further ZFS version at the moment.
I am also removing myself from maintenance of any further ZFS versions as I am
planning to quit ZFS maintenance at some point.
In the meantime, for users like me who depend on ZFS for critical operations, here is a ZFS version
that is known to work for LTS kernels.
