Cleanup the usage of deprecated CONF.network_api_class in hyper-v driver

[Alex Xu]

As we already deprecated network_api_class config option in this series patches https://review.openstack.org/#/q/topic:deprecate_managers

But in hyper-v driver, there still have a reference to the network_api_class config option. We should cleanup it.

[OpenStack Infra (hudson-openstack)]

Fix proposed to branch: master
Review: https://review.openstack.org/289457

[OpenStack Infra (hudson-openstack)]

Reviewed: https://review.openstack.org/289457
Committed: https://git.openstack.org/cgit/openstack/nova/commit/?id=61a90eaf84e9cad2d8783ab2cfea4575e2dece70
Submitter: Jenkins
Branch: master

commit 61a90eaf84e9cad2d8783ab2cfea4575e2dece70
Author: Sean Dague <email address hidden>
Date: Mon Mar 7 11:58:57 2016 -0500

    Fix hyperv use of deprecated network_api_class

    Hyperv driver had some residual use of network_api_class after it was
    deprecated in the core. This makes hyperv use nova.network.is_neutron
    for selecting its network drivers.

    Change-Id: Icfcafd031a793a4713c2997adc5c84bb9c9864fe
    Closes-Bug: #1554059

[Thierry Carrez (ttx)]

This issue was fixed in the openstack/nova 13.0.0.0rc1 release candidate.