bnx2x: ethtool publishes link partners speed and FC

Following the changes in the ethtool source code, this patch enables
the bnx2x driver to publish the Link partner's capabilities s, when ethtool
is used on an interface which completed autoneg.

Signed-off-by: Yuval Mintz <yuvalmin@broadcom.com>
Signed-off-by: Yaniv Rosner <yaniv.rosner@broadcom.com>
Signed-off-by: Eilon Greenstein <eilong@broadcom.com>
Signed-off-by: David S. Miller <davem@davemloft.net>