mask notifiers are never called without msix,
so devices with backend masking like vhost don't work.
Call mask notifiers explicitly at
startup/cleanup to make it work.
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Tested-by: Alexander Graf <agraf@suse.de>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>