jfs: Fix array index bounds check in dbAdjTree

commit c61b3e4839007668360ed8b87d7da96d2e59fc6c upstream.

Bounds checking tools can flag a bug in dbAdjTree() for an array index
out of bounds in dmt_stree. Since dmt_stree can refer to the stree in
both structures dmaptree and dmapctl, use the larger array to eliminate
the false positive.

Signed-off-by: Dave Kleikamp <dave.kleikamp@oracle.com>
Reported-by: butt3rflyh4ck <butterflyhuangxx@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>