[util] Add `genbnx2' util to create firmware structure from the original Option ROMs

Signed-off-by: Anton D. Kachalov <mouse@yandex-team.ru>
Put Broadcom's 5706 (Dell Poweredge 1950) and 5709 (Huawei Tecal RH1285) Option ROM

Signed-off-by: Anton D. Kachalov <mouse@yandex-team.ru>
[drivers/net/bnx2] Update driver from Dewyatt's repo. Update firmware structure from original BCM OPROMs

Signed-off-by: Anton D. Kachalov <mouse@yandex-team.ru>