This fixes ntuple calculation for IPv6 active open request for T5
adapter.  And also removes an duplicate line which got added in commit
92e7ae71 ("iw_cxgb4: Choose appropriate hw mtu index and ISS for
iWARP connections")
Signed-off-by: Hariprasad Shenai <hariprasad@chelsio.com>
Signed-off-by: Roland Dreier <roland@purestorage.com>