qed: Add support for multi function mode with 802.1ad tagging.

The patch adds support for new Multi function mode wherein the traffic
classification is done based on the 802.1ad tagging and the outer vlan tag
provided by the management firmware.

Signed-off-by: Sudarsana Reddy Kalluru <Sudarsana.Kalluru@cavium.com>
Signed-off-by: Ariel Elior <ariel.elior@cavium.com>
Signed-off-by: David S. Miller <davem@davemloft.net>