When certain directories, like /tmp, get mounted over, FCOS/Linux can
act in unexpected ways. Added a sanity check for a list of directories
think might be impacted by this. Also, moved the volume parsing earlier
in the init process so we can catch problems before the expensive
decompression of machine images.
The following destinations are forbidden for volumes:
`/bin`, `/boot`, `/dev`, `/etc`, `/home`, `/proc`, `/root`, `/run`, `/sbin`, `/sys`, `/tmp`, `/usr`, and `/var`. Subdirectories
Fixes: #18230
Signed-off-by: Brent Baude <bbaude@redhat.com>