main/busybox: fix find -xdev -delete
find with -depth (implied by -delete) ignores -xdev, which has been a long standing bug.
This bite us in scripts' cleanup, so would appreciate getting it fixed
as there is no easy workaround...
(for example, something like this, ignoring errors:
unshare -m sh -c 'mount --bind "$1" /mnt && rm -rf /mnt' -- "$dir" && rmdir "$dir"
)
Patch was sent upstream as well, but no reply yet (which I'd claim is not that surprising)
Link: https://bugs.busybox.net/show_bug.cgi?id=5756
Link: http://lists.busybox.net/pipermail/busybox/2023-September/090479.html