i40e: Reset the VF upon conflicting VLAN configuration

If a host VMM administrator hoses his VF by assigning a port VLAN after
it is already up and running with implicit permission to set local
VLANs then we print a message warning the host administrator that the
VF driver needs to be reloaded.

In addition we need to knock the VF offline so that it does not continue
to receive traffic not on the port VLAN assigned to it.  So we reset the
VF.  The VF will cease operation and the administrator will be forced to
unload and reload the VF driver to make it work again.

Change-ID: Iae1ae006b244e74e30a4ee546b3c5fca5cfb40aa
Signed-off-by: Greg Rose <gregory.v.rose@intel.com>
Signed-off-by: Catherine Sullivan <catherine.sullivan@intel.com>
Tested-by: Sibai Li <sibai.li@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>