cxgb4: add tc flower match support for vlan

Add support for matching on vlan tci.  Construct vlan tci match param
based on vlan-id and vlan-pcp values supplied by tc.

Signed-off-by: Kumar Sanghvi <kumaras@chelsio.com>
Signed-off-by: Rahul Lakkireddy <rahul.lakkireddy@chelsio.com>
Signed-off-by: Ganesh Goudar <ganeshgr@chelsio.com>
Signed-off-by: David S. Miller <davem@davemloft.net>