Add Support for Changed Block Tracking in PV Snaphosts

[nikobo]

We would like to have support of the Changed Block Tracking with the HPE CSI driver.
This feature has been announced last september in the K8S blog : https://kubernetes.io/blog/2025/09/25/csi-changed-block-tracking/

We're excited to announce the alpha support for a changed block tracking mechanism. This enhances the Kubernetes storage ecosystem by providing an efficient way for CSI storage drivers to identify changed blocks in PersistentVolume snapshots. With a driver that can use the feature, you could benefit from faster and more resource-efficient backup operations.

[datamattsson]

Thanks for the interest in the HPE CSI Driver. AFAICT, CBT is still in Alpha upstream and OpenShift has it listed as a dev preview? We normally implement upstream features once the APIs are stable and there's customer demand for the feature.