Added restrictions around calling MSCCL++ collectives

[corey-derochie-amd]

Details

Do not mention proprietary info or link to internal work items in this PR.

Work item: Internal

What were the changes?
Applied the same restriction on message sizes to MSCCL++ AllGather as for MSCCL++ AllReduce.

Why were the changes made?
MSCCL++ was being used for invalid message sizes in certain unit tests, causing failures.

Approval Checklist

Do not approve until these items are satisfied.

• [ ] Verify the CHANGELOG has been updated, if
  • there are any NCCL API version changes,
  • any changes impact library users, and/or
  • any changes impact any other ROCm library.