ARO: Add capability for Azure VMs to be created with ephemeral disks

User Story:

As a user of HyperShift, I want to be able to create Azure VMs with ephemeral disks, so that I can achieve higher IOPS.

Note: AKS also defaults to using them.

Acceptance Criteria:

Description of criteria:

• Verify upstream documentation exists on how to setup Azure VMs with ephemeral disks
• HyperShift documentation added on how to setup Azure VMs with ephemeral disks
• Capability to create clusters with Azure VMs with ephemeral disks exists
• Capability to create NodePools with Azure VMs with ephemeral disks exists

Out of Scope:

N/A

Engineering Details:

• Upstream documentation exists in CAPZ here.

This does not require a design proposal.
This does not require a feature gate.