This commit is an extension of fix for 29325 based on the review comment.
In this commit, the quota size for btrfs is kept in `/var/lib/docker/btrfs/quotas`
so that a daemon restart keeps quota.
Signed-off-by: Yong Tang <yong.tang.github@outlook.com>
Upstream-commit: 16328cc207a493ecff0cabc11ebf51e958131418
Component: engine