When ring size or enqueue packets not aligned with batch number, it is
possible that descs update still kept in shadowed used structure when
batched enqueue. Fix this issue by flushing remained shadowed used descs
before batch flush.
Fixes: f41516c309 ("vhost: flush batched enqueue descs directly")
Cc: stable@dpdk.org
Signed-off-by: Marvin Liu <yong.liu@intel.com>
Reviewed-by: Maxime Coquelin <maxime.coquelin@redhat.com>