bnx2x: Fix over current port display

On 57712 chip, port number is enumerated per engine, so it requires adjustment in port display to the user.

Signed-off-by: Yaniv Rosner <yanivr@broadcom.com>
Signed-off-by: Eilon Greenstein <eilong@broadcom.com>
Signed-off-by: David S. Miller <davem@davemloft.net>