[Rebase & FF] Adding MM communication buffer validation

[kuqin12]

Description

This change adds a few validation before using the derived buffer size from message length.

However, note that the buffer size is not used directly due to a check after that. Thus the MM communication agent or the core in MM will not consume the value directly. But this would cause the MM handler to potentially receive a huge message in length.

For details on how to complete these options and their meaning refer to CONTRIBUTING.md.

• Impacts functionality?
• Impacts security?
• Breaking change?
• Includes tests?
• Includes documentation?

How This Was Tested

This is currently being tested.

Integration Instructions

N/A

[mu-automation]

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