init-ceph: do not stop start on first failure

When starting we often loop over many daemon instances.  Currently we stop
on the first error and do not try to start other daemons.

Instead, try them all, but return a failure if anything did not start.

Fixes: #2545
Signed-off-by: Sage Weil <sage@inktank.com>
Reviewed-by: Gary Lowell <gary.lowell@inktank.com>