xfs: fix iunlock calls in xrep_adoption_trans_alloc

If the transaction allocation in xrep_adoption_trans_alloc fails, we
should drop only the locks that we took.  In this case this is
ILOCK_EXCL of both the orphanage and the file being repaired.  Dropping
any IOLOCK here is incorrect.

Found by fuzzing u3.sfdir3.list[1].name = zeroes in xfs/1546.
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>

fs/xfs/scrub/orphanage.c

@@ -382,7 +382,7 @@ xrep_adoption_trans_alloc(
 out_cancel:
 	xchk_trans_cancel(sc);
 	xrep_orphanage_iunlock(sc, XFS_ILOCK_EXCL);
-	xrep_orphanage_iunlock(sc, XFS_IOLOCK_EXCL);
+	xchk_iunlock(sc, XFS_ILOCK_EXCL);
 	return error;
 }