mount lvm snapshot failed when filesystem recovery is required

[hao]

Freezer-agent backup with lvm snapshot will fail if the xfs filesystem in the snapshot need recovery.

- reproduce steps
# freezer-agent --debug --snapshot mysql_lv --lvm-srcvol /dev/cl/var --lvm-volgroup cl --path-to-backup /var/lib/mysql --mysql-conf /root/.freezer/freezer-mysql.conf --storage swift --container freezer_mysql-backup-prod --mode mysql --backup-name mysql-test8 --exclude "\*.lock"

Critical Error: lvm snapshot mounting error: mount: cannot mount /dev/mapper/cl-freezer_backup_snap_32bfc5352ebf4b56a21448582822b3af read-only

- dmesg details
# dmesg |tail
[11154.739393] XFS (dm-14): Mounting V5 Filesystem
[11154.771596] XFS (dm-14): recovery required on read-only device.
[11154.771600] XFS (dm-14): write access unavailable, cannot proceed.
[11154.771602] XFS (dm-14): log mount/recovery failed: error -30
[11154.771646] XFS (dm-14): log mount failed

[OpenStack Infra (hudson-openstack)]

Fix proposed to branch: master
Review: https://review.opendev.org/722361