bnx2x: populate skb->l4_rxhash

l4_rxhash is set on skb when rxhash is obtained from canonical 4-tuple
over transport ports/addresses.

We can set skb->l4_rxhash for all incoming TCP packets on bnx2x for
free, as cqe status contains a hash type information.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: Eilon Greenstein <eilong@broadcom.com>
Cc: Willem de Bruijn <willemb@google.com>
Acked-by: Eilon Greenstein <eilong@broadcom.com>
Signed-off-by: David S. Miller <davem@davemloft.net>