fs2bs: skip migration when a mix of fs and bs is detected

fs2bs: skip migration when a mix of fs and bs is detected

Since the default of `osd_objectstore` has changed as of 3.2, some
deployments might have a mix of filestore and bluestore OSDs on a same
node. In some specific cases, there's a possibility that a filestore OSD
shares a journal/db device with a bluestore OSD. We shouldn't try to
redeploy in this context because ceph-volume will complain. (either
because in lvm batch you can't pass partition or about gpt header).
The safest option is to skip the migration on the node when such a mix
is detected or force all osds including those already using bluestore
(option `force_filestore_to_bluestore=True` has to be passed as an extra var).
If all OSDs are using filestore, then they will be migrated to
bluestore.

Closes: https://bugzilla.redhat.com/show_bug.cgi?id=1875777
Signed-off-by: Guillaume Abrioux <gabrioux@redhat.com>