With this, users can select disks with LVM on it for journal/db devices,
which will be necessary for ceph nautilus, since there
journals/db/wal will be put on an LV
of course when creating an osd, we have to detect if that
is ok (probably based on the vg name on it)
Signed-off-by: Dominik Csapak <d.csapak@proxmox.com>
cd814c0453