Add support for paravirtualized launch volume attachment

[kdw174]

What would you like to be added:
Recently support was added for configuring paravirtualized launch volume attachments at instance creation.

The cluster-api provider only supports iscsi launch volume attachments today.

Why is this needed:
We have a need for Ultra High Performance volumes that are created with the instance. Today, we have to create the instance with the volume and ISCSI attachment, then run post kubeadm commands to detach and reattach the volume as paravirtualized volume attachment. This would greatly simplify the setup required here by attaching the volume as a paravirtualized attachment at instance creation.

[eshneken]

Is this enhancement for boot volumes or block volumes? Can you share a sample YAML snippet of how you create the cluster today with ISCSI?

[kdw174]

This is a block volume. Here's a snippet from an ocimachinetemplate

spec:
  template:
    spec:
      launchVolumeAttachments:
      - launchIscsiVolumeAttachment:
          device: /dev/oracleoci/oraclevdb
          launchCreateVolumeFromAttributes:
            sizeInGBs: 1500
            vpusPerGB: 60
        volumeType: iscsi