Bug 2119715

.Complex OSD deployment or replacement with shared DB devices now does not need to be done all at once Previously, devices already used as `db` devices for previous OSDs were filtered out as unavailable devices, when `cephadm` created OSDs. As a result, complex OSD deployment where all the OSDs that were meant to use a device as their DB, but were not deployed at once, would not work as the DB device would be filtered out when creating subsequent OSDs even though they should not be according to the OSD specification. With this fix, complex OSD deployment with shared DB devices now does not need to be done all at once. If users update an OSD specification to include additional data devices to be paired up with the already listed db devices in the specifications, `cephadm` should be able to create these new OSDs.