(cherry picked from commit ec87ef43)

All references to the embedded ceph_connection come from the msgr
workqueue, which is drained prior to mon_client destruction.  That
means we can ignore con refcounting entirely.
Signed-off-by: Sage Weil <sage@newdream.net>
Reviewed-by: Alex Elder <elder@inktank.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>