An unwitting user may apply the KOLLA_CEPH_OSD[_CACHE]_BOOTSTRAP label
to a partition assuming it will only use that partition for Ceph, and
end up wiping out their disk.

This change adds a layer of checking to this scenario to try and help
avoid a disaster scenario.

Closes-Bug: 1599103
DocImpact

Change-Id: Ibb9fb42f87a76bc02165ec0b93b60234bad8747a