storwize: empty io groups cannot be used

[Avishay Traeger]

The Storwize driver mistakenly checks on startup if vdisk_count > 0 for io groups, and fails if this is not the case. This means that controllers with empty io groups cannot be used.

[OpenStack Infra (hudson-openstack)]

Fix proposed to branch: master
Review: https://review.openstack.org/52031

[OpenStack Infra (hudson-openstack)]

Reviewed: https://review.openstack.org/52031
Committed: http://github.com/openstack/cinder/commit/cf16029b69f50af1bc2e8627af5bc65ffac24992
Submitter: Jenkins
Branch: master

commit cf16029b69f50af1bc2e8627af5bc65ffac24992
Author: Avishay Traeger <email address hidden>
Date: Wed Oct 16 11:14:22 2013 +0300

    Storwize: Fix iogrp availability check

    Do not check if vdisk_count is greater than zero to determine iogrp
    availability. This is wrong, and leads to the driver not being able to
    use empty iogrps.

    Change-Id: Ia73189a11cfcc0641c1527293675361c4e78443f
    Closes-Bug: #1240395

[OpenStack Infra (hudson-openstack)]

Fix proposed to branch: stable/havana
Review: https://review.openstack.org/52876

[OpenStack Infra (hudson-openstack)]

Reviewed: https://review.openstack.org/52876
Committed: http://github.com/openstack/cinder/commit/751e0faad47a86d662b21873ddde1b2b331b6b48
Submitter: Jenkins
Branch: stable/havana

commit 751e0faad47a86d662b21873ddde1b2b331b6b48
Author: Avishay Traeger <email address hidden>
Date: Wed Oct 16 11:14:22 2013 +0300

    Storwize: Fix iogrp availability check

    Do not check if vdisk_count is greater than zero to determine iogrp
    availability. This is wrong, and leads to the driver not being able to
    use empty iogrps.

    Closes-Bug: #1240395
    Cherry-pick from https://review.openstack.org/#/c/52031/

    Change-Id: I50456a0c618103f919ef0da7fb9e44b77a1d9bff