Cinder and Glance rbd chunk size should be the same and configurable

[Giulio Fidente]

Glance and Cinder appear to be using different defaults for the rbd_chunk_size while they should not or operations which involve snapshotting/cloning images will fail.

This is especially important when the Ceph cluster is at the Pacific level, where such a thing is enforced with the cluster returning error if it isn't, see https://review.opendev.org/c/openstack/cinder/+/804265

While recent versions of Cinder are trying to workaround this by adopting whichever chunk size is in use for the source image, we should configure the services to use by the same value and eventually make it configurable for performance reasons.

puppet-glance and puppet-cinder support this already

https://github.com/openstack/puppet-glance/blob/master/manifests/backend/multistore/rbd.pp#L32

https://github.com/openstack/puppet-cinder/blob/master/manifests/backend/rbd.pp#L62

[OpenStack Infra (hudson-openstack)]

Fix proposed to branch: master
Review: https://review.opendev.org/c/openstack/puppet-tripleo/+/824520

[OpenStack Infra (hudson-openstack)]

Fix proposed to branch: master
Review: https://review.opendev.org/c/openstack/tripleo-heat-templates/+/824525

[OpenStack Infra (hudson-openstack)]

Change abandoned by "Brent Eagles <email address hidden>" on branch: master
Review: https://review.opendev.org/c/openstack/puppet-tripleo/+/824520
Reason: -1'd, inactive > 1y, conflicts

[OpenStack Infra (hudson-openstack)]

Change abandoned by "Ghanshyam <email address hidden>" on branch: master
Review: https://review.opendev.org/c/openstack/tripleo-heat-templates/+/824525
Reason: TrieplO project is retiring now, for details, please see https://review.opendev.org/c/openstack/governance/+/905145 or reach out to OpenStack TC.