ceph-volume: create LVs when using partitions

ceph-volume: create LVs when using partitions

commit [1] introduced a behavior change.
`ceph-volume lvm prepare` used to create VGs/LVs when it was passed partitions
for db and/or wal devices. Since commit [1] has been introduced, it made ceph-volume
consume the partition directly, it doesn't create LV anymore. Although this
doesn't prevent from creating OSDs, this is a behavior change.

Fixes: https://tracker.ceph.com/issues/65477
[1] 1e7223281fa044c9653633e305c0b344e4c9b3a4

Signed-off-by: Guillaume Abrioux <gabrioux@ibm.com>
(cherry picked from commit 11f0173f1299ed6d137159dcf62c4a7a9fd20f82)