Configure additionalBlockDevice via cluster variable

[jschoone]

What this PR does / why we need it:

This makes it possible to add more Block Devices to worker nodes

Which issue(s) this PR fixes (optional, in fixes #<issue number>(, fixes #<issue_number>, ...) format, will close the issue(s) when PR gets merged):
Fixes #

Special notes for your reviewer:

Please confirm that if this PR changes any image versions, then that's the sole change this PR makes.

TODOs:

• squash commits
• include documentation
• add unit tests

[jschoone]

Hi @garloff , the feature to add block devices can be tested with Cluster Stacks registry.scs.community/kaas/cluster-stacks:openstack-scs-1-32-v0-git-d1d35dc

Example Cluster definition, see the override at the end:

apiVersion: cluster.x-k8s.io/v1beta1
kind: Cluster
metadata:
  name: my-cluster
  namespace: cluster
  labels:
    managed-secret: cloud-config
spec:
  clusterNetwork:
    pods:
      cidrBlocks:
      - "172.16.0.0/16"
    serviceDomain: cluster.local
    services:
      cidrBlocks:
      - "10.96.0.0/12"
  topology:
    class: openstack-scs-1-32-v0-git.d1d35dc
    controlPlane:
      replicas: 1
    version: v1.32.1
    workers:
      machineDeployments:
        - class: default-worker
          name: md-0
          replicas: 1
          variables:
            overrides:
            - name: additionalBlockDevices
              value:
              # Adds /dev/sdb with default 20GiB
              - name: data
              # Adds /dev/sdc with 50GiB
              - name: logs
                sizeGiB: 50

[garloff]

Nice feature.
(Even though I suspect that typically worker nodes should NOT use this and storage needs rather be fulfilled by using PVs.)

[garloff]

Additional notes:

1. Should there be some documentation?
2. I tested it and it works like a charm.

[garloff]

This was part of #232 and can thus be closed, no, @jschoone?

[jschoone]

This was part of #232 and can thus be closed, no, @jschoone?

Yes, I'll close it