Move multipath structure's 'lock' and 'queue_size' members to eliminate
two 4-byte holes. Also use a bit within a single unsigned int for each
existing flag (saves 8-bytes). This allows future flags to be added
without each consuming an unsigned int.
Signed-off-by: Mike Snitzer <snitzer@redhat.com> Acked-by: Hannes Reinecke <hare@suse.de> Signed-off-by: Alasdair G Kergon <agk@redhat.com>