xfs: metapath scrubber should use the already loaded inodes

Don't waste time in xchk_setup_metapath_dqinode doing a second lookup of
the quota inodes, just grab them from the quotainfo structure.  The
whole point of this scrubber is to make sure that the dirents exist, so
it's completely silly to do lookups.

Cc: <stable@vger.kernel.org> # v6.13-rc1
Fixes: 128a0552 ("xfs: scrub quota file metapaths")
Signed-off-by: "Darrick J. Wong" <djwong@kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>