bnx2x: EEE status is read locally

This patch aligns the EEE status with that of all other link properties,
by changing the way its accessed - instead of a direct read to the shared
memory, each function maintain its own copy locally.

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