gopowermax updates to support powermax unit tests

[bharathsreekanth]

Description

Minor enhancements to gopowermax to aid csi-powermax tests

GitHub Issues

List the GitHub issues impacted by this PR:

GitHub Issue #

Checklist:

• Have you run format,vet & lint checks against your submission?
• Have you made sure that the code compiles?
• Did you run the unit & integration tests successfully?
• Have you maintained at least 90% code coverage?
• Have you commented your code, particularly in hard-to-understand areas
• Have you done corresponding changes to the documentation
• Did you run tests in a real Kubernetes cluster?
• Have you maintained at least 90% code coverage?
• Backward compatibility is not broken

How Has This Been Tested?

Unit tested csi-powermax with commit ID from these changes.

[lukeatdell]

Is this variable accessed from unit tests in csi-powermax?

[bharathsreekanth]

yes.