Bulk update storage tiers for all volumes attached to a single VM

Currently, we can change the storage tier for volumes in PowerVS via the IBM Cloud Web UI or CLI. However, this must be done individually for each volume.

IBM i VMs typically have a large number of volumes to ensure optimal I/O performance. As a result, when we need to change the storage tier for an IBM i VM, we must repeat the same operation many times.

If a feature were provided to change the storage tier for all volumes attached to a VM at once (bulk update), it would significantly improve our work efficiency and reduce the risk of manual errors.