libvirt: remove 'vif_driver' config parameter

[OpenStack Infra]

https://review.openstack.org/109266
commit 7561c8ded211d53e8745d1420a73b82bd0fc35cf
Author: Daniel P. Berrange <email address hidden>
Date: Thu Jul 24 11:53:47 2014 +0100

    libvirt: remove 'vif_driver' config parameter

    The 'vif_driver' config parameter was deprecated in the
    previous cycle, so can be deleted now.

    The two places in the test file which were overriding
    the 'vif_driver' config parameter were redundant as
    mocking already ensured the real VIF driver module
    was not exercised.

    The FakeVIFDriver class is thus no longer required, and
    the FakeIptablesFirewallDriver class was already not
    required, so both are deleted.

    DocImpact
    Related-bug: #1302796
    Change-Id: I75519266ffc65df92efd20badfeaf88ac0d66f8a

[Andreas Jaeger (jaegerandi)]

This needs regeneration of our generated tables.

[Andreas Jaeger (jaegerandi)]

has been removed.