mount: make checks on perpetual mount units more lax
We don#t really care where perpetual mounts are mounted from, since they
have to exist since before we run anyway.
(cherry picked from commit
0879fbd6fedc2f813aebcb1a4eba005a99525bde)
Gbp-Pq: Name mount-make-checks-on-perpetual-mount-units-more-lax.patch
core: never allow perpetual units to be masked
Fixes: #14550
(cherry picked from commit
88414eed6f45f738ae765d9f72d67c6dc5a51950)
Gbp-Pq: Name core-never-allow-perpetual-units-to-be-masked.patch