dm raid: display a consistent copy of the MD status via raid_status()
The MD sync thread updates recovery flags providing state of any
running, idle, frozen, recovering, reshaping, ... activity it performs
and updates respective flags asynchronously versus dm processing
raid_status(). To close that race window, take a single copy of the
flags and pass it into its callees.
Signed-off-by: Heinz Mauelshagen <heinzm@redhat.com> Signed-off-by: Mike Snitzer <snitzer@redhat.com>