qlcnic: Support VLAN id config.

o Add support for VLAN id configuration per VF using
  iproute2 tool.
o VLAN id's 1-4094 are treated as PVID by the PF and
  Guest VLAN tagging is not allowed by default.
o PVID is disabled when the VLAN id is set to 0
o Guest VLAN tagging is allowed when the VLAN id is set to 4095.
o Only one Guest VLAN id  is supported.
o VLAN id can be changed only when the VF driver is not loaded.

Signed-off-by: Manish Chopra <manish.chopra@qlogic.com>
Signed-off-by: Sucheta Chakraborty <sucheta.chakraborty@qlogic.com>
Signed-off-by: Rajesh Borundia <rajesh.borundia@qlogic.com>
Signed-off-by: David S. Miller <davem@davemloft.net>