It's quite convinient to expose /var/log/ceph so that we can decide to
activate logs locally on the machine and see what's going on.
This is only a placeholder when a daemon is stuck crashlooping and we
want to allow administrator to gather log files.
We still do not log on file but this can be activated via a config
option passed to the centralized config option store.
For some daemons, which typically do not store any data (rgw, rbd-mirror
and mds) we had to propagate dataDirHostPath from the cluster spec to
each creation call so that the bindmount can happen.
Fixes: https://github.com/rook/rook/issues/2881
Signed-off-by: Sébastien Han <seb@redhat.com>