s390/virtio-ccw: remove redundant call to blockdev_mark_auto_del

blockdev_mark_auto_del is already called in virtio-blk-exit.
Remove the redundant call.
Signed-off-by: NChristian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: NJens Freimann <jfrei@linux.vnet.ibm.com>
Signed-off-by: NAlexander Graf <agraf@suse.de>

hw/s390x/virtio-ccw.c

@@ -585,7 +585,6 @@ static int virtio_ccw_blk_init(VirtioCcwDevice *dev)
 static int virtio_ccw_blk_exit(VirtioCcwDevice *dev)
 {
     virtio_blk_exit(dev->vdev);
-    blockdev_mark_auto_del(dev->blk.conf.bs);
     return virtio_ccw_exit(dev);
 }