Add support for OpenStack CSI drivers topology keys

[kayrus]

Thank you for contributing to Velero!

Please add a summary of your change

The change adds support for the OpenStack CSI drivers topology keys:

• cinder: https://github.com/kubernetes/cloud-provider-openstack/blob/8b6636c5088851bd1b934ae9ca9dc283de247609/pkg/csi/cinder/driver.go#L33-L34
• manila: https://github.com/kubernetes/cloud-provider-openstack/blob/8b6636c5088851bd1b934ae9ca9dc283de247609/pkg/csi/manila/driver.go#L90

Does your change fix a particular issue?

Fixes #6440

Please indicate you've done the following:

• Accepted the DCO. Commits without the DCO will delay acceptance.
• Created a changelog file or added /kind changelog-not-required as a comment on this pull request.
• Updated the corresponding documentation in site/content/docs/main.

[codecov-commenter]

Codecov Report

Merging #6464 (e71ee0c) into main (e54a8af) will not change coverage.
The diff coverage is 100.00%.

@@           Coverage Diff           @@
##             main    #6464   +/-   ##
=======================================
  Coverage   60.18%   60.18%           
=======================================
  Files         229      229           
  Lines       24215    24215           
=======================================
  Hits        14575    14575           
  Misses       8632     8632           
  Partials     1008     1008           

Impacted Files	Coverage Δ
pkg/backup/item_backupper.go	73.74% <100.00%> (ø)

[kayrus]

@Lyndon-Li @shubham-pampattiwar thanks a lot for a quick merge. Do you have an estimate when a new release is planned?

[Lyndon-Li]

@kayrus
See this tentative timeline for v1.12 https://github.com/vmware-tanzu/velero/wiki/1.12-Roadmap.

[kayrus]

@Lyndon-Li do you think this PR can be backported to the current stable version?