Delete the libvirt volume_drivers config parameter

[Daniel Berrange]

A followup from

  https://bugs.launchpad.net/nova/+bug/1362191

This bug is to track the actual deletion of the volume_drivers config parameter.

[jichenjc (jichenjc)]

To be done in L release

[OpenStack Infra (hudson-openstack)]

Fix proposed to branch: master
Review: https://review.openstack.org/168511

[OpenStack Infra (hudson-openstack)]

Reviewed: https://review.openstack.org/168511
Committed: https://git.openstack.org/cgit/openstack/nova/commit/?id=3bcaf68357d361100cb3ac35b3a5504627db8f0e
Submitter: Jenkins
Branch: master

commit 3bcaf68357d361100cb3ac35b3a5504627db8f0e
Author: jichenjc <email address hidden>
Date: Sun Mar 22 23:23:04 2015 +0800

    libvirt: remove volume_drivers config param

    Copied commit message from
    commit I1f884f36e24fe478922671ca3eaf6b7c21fd8a5a

    The 'volumes_drivers' parameter does the same job as the
    'vif_driver' parameter, but for volumes instead of vifs.

    The API for the LibvirtBaseVolumeDriver class is not
    considered to be a public extension point. As such it
    is not required or expected to remain compatible across
    releases.

    The main reason for its existance is for people who are
    developing new cinder drivers, to be able to write out
    of tree nova volume drivers. The recommended practice
    is to instead work in-tree to nova on a branch. This is
    an approach that would be required in order to submit
    the work for review and eventual merge in any case.

    commit I1f884f36e24fe478922671ca3eaf6b7c21fd8a5a
    deprecated it and during the discussion the actually target
    is Kilo. But it's K-3 so more reasonable target is
    Liberty.

    DocImpact: libvirt.volume_drivers config param is removed.

    Closes-Bug: #1371175

    Change-Id: I832820499ec3304132379ad9b9d1ee92c5a75b61