bnx2x: Add support for 4-tupple UDP RSS

This change enables to control via ethtool whether to do UDP RSS on 2-tupple
(IP source / destination only) or on 4-tupple (include UDP source / destination
port). It also enables to read back the RSS configuration.

Signed-off-by: Merav Sicron <meravs@broadcom.com>
Signed-off-by: Eilon Greenstein <eilong@broadcom.com>
Signed-off-by: David S. Miller <davem@davemloft.net>