[Feature request] Use `ceph-volume` to manage OSDs

So, I'm converting my existing Ceph cluster to use Skyflake. One issue that is stopping me from using it to deploy OSDs with, however, is that I require full disk encryption for each OSD.

I deployed my OSDs via `ceph-volume create`, with the `--dmcrypt` flag. This sets up each OSD to be encrypted via LUKS. At boot, `ceph-volume activate` grabs the LUKS keys from a Ceph monitor, passes them to `dm-crypt`, and then proceeds as normal in activating the OSDs.

Existing OSDs can be easily converted to use `ceph-volume`; so is it possible to change the OSD management logic to use `ceph-volume` instead? I suspect it would greatly simplify the implementation.

Start by locating Skyflake's current OSD management entry point and compare it with the ceph-volume create and activate flow described in the issue. Trace how OSD deployment and boot-time activation currently work, then verify that the resulting management supports encrypted OSDs and the requested ceph-volume workflow.

Written by the indexing model from the issue text.