Let's make our units more robust to being added to an initrd:
1. systemd-boot-update only makes sense if sd-boot is available in /usr/
to copy into the ESP. This is generally not the case in initrds, and
even if it was, we shouldn't update the ESP from the initrd, but from
the host instead.
2. The rfkill services save/restore rfkill state, but that information
is only available once /var/ is mounted, which generally happens
after the initrd transition.
3. utmp management is partly in /var/, and legacy anyway, hence don't
bother with it in the initrd.
Follow-up for 123c0e24dd.
Note, the entry was originally added for IdeaPad Flex 5 in
21b589a155.
Then, a bug introduced by 19db450f3a.
But, when it was fixed by 738a195bd5,
the glob becomes too stricter, and another variant was added by
123c0e24dd.
Follow-up for 017a7ba4f4
Before this commit, when a unit that is restarting propagates stop
to other units, it can also depend on them, which results in
job type conflict and thus failure to pull in the dependencies.
So, let's introduce a new dependency atom UNIT_ATOM_PROPAGATE_STOP_GRACEFUL,
and use it for PropagatesStopTo=. It will enqueue a restart job if
there's already a start job, which meets the ultimate goal and avoids
job type conflict.
Fixes#26839
