Goal

With CNV-57873 we allow disks to be hot-plugged if they are of type virtio(-blk), not only virtio-scsi.

We need to change the UI to:
1. Allow to select virtio as the bus when adding a hot-plug disk
2. Make virtio the default selection when adding a hot-plug disk

User Stories

• High-Level goal-based user story, with context.
  "As a <VM owner/cluster administrator>, I want <to Achieve Some Goal>, so that <Some Reason/Context>."
• another user story

Non-Requirements

• List of things not included in this epic, to alleviate any doubt raised during the grooming process.

Notes

• Any additional details or decisions made/needed