bnx2x: Using the HW 5th lane

This 1G interface (on top of the 4 lanes 10G interface) requires additional
setting to work in CL45

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>