implement ndo_set_vf_vlan for mgmt netdevice to configure
the PCIe VF.

Original work by: Casey Leedom <leedom@chelsio.com>
Signed-off-by: NGanesh Goudar <ganeshgr@chelsio.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>