vstart.sh: make crush location match up with what init-ceph does

This makes is to that ./init-ceph restart osd.0 won't modify the CRUSH
tree.  And in any case, the localhost/localrack thing we were doing before
was pretty useless.

Signed-off-by: Sage Weil <sage@inktank.com>
os/FileStore: reset journal state on umount

We observed a sequence like:

 - replay journal
   - sets JournalingObjectStore applied_op_seq
 - umount
 - mount
   - initiate commit with prevous applied_op_seq
 - replay journal
   - commit finishes
   - on replay commit, we fail assert op > committed_seq

Although strictly speaking the assert failure is harmless here, in general
we should not let state leak through from a previous mount into this
mount or else assertions are in general more difficult to reason about.

Fixes: #8019
Signed-off-by: Sage Weil <sage@inktank.com>
Merge pull request #1625 from ceph/wip-8019

osd: fix journal umount/mount weirdness

Reviewed-by: Samuel Just <sam.just@inktank.com>