Quota reservations are supposed to account for the blocks that might be
allocated due to a bmap btree split. Reflink doesn't do this, so fix
this to make the quota accounting more accurate before we start
rearranging things.
Fixes: 862bb360ef56 ("xfs: reflink extents from one file to another") Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Reviewed-by: Brian Foster <bfoster@redhat.com>