Inherit from neutron-lib "LinuxInterfaceDriver" class
Inherit from neutron-lib "LinuxInterfaceDriver" class

"LinuxInterfaceDriver" methods "plug_new" and "unplug" are implemented
in other projects than Neutron. In order to avoid method signature
changes that could affect to those projects implementing this class,
the base metaclass is now in neutron-lib.

Change-Id: I2ce790b8796c3aa65c771d765a20938e8d56c0bc

mahak/neutron,openstack/neutron,mahak/neutron,openstack/neutron,mahak/neutron,openstack/neutron