dm thin metadata: Fix trivial math error in on-disk format documentation

Signed-off-by: Jeffle Xu <jefflexu@linux.alibaba.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
This commit is contained in:
Jeffle Xu 2019-12-30 10:54:32 +08:00 • committed by Mike Snitzer
commit 4306904053