Fix MMI entrypoint code for standalone binary integration

[kuqin12]

Preface

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Description

The existing nasmb code has various issues that cannot launch SMM properly.

This change fixed both the assembly code that can bring the system into x64 mode, as well as fixing the fixup logic from the initialization code to patch the appropriate content into the MMI entry routine.

For each item, place an "x" in between [ and ] if true. Example: [x]. (you can also check items in the GitHub UI)

• [x] Impacts functionality?
  • Functionality - Does the change ultimately impact how firmware functions?
  • Examples: Add a new library, publish a new PPI, update an algorithm, ...
• [ ] Impacts security?
  • Security - Does the change have a direct security impact on an application, flow, or firmware?
  • Examples: Crypto algorithm change, buffer overflow fix, parameter validation improvement, ...
• [ ] Breaking change?
  • Breaking change - Will anyone consuming this change experience a break in build or boot behavior?
  • Examples: Add a new library class, move a module to a different repo, call a function in a new library class in a pre-existing module, ...
• [ ] Includes tests?
  • Tests - Does the change include any explicit test code?
  • Examples: Unit tests, integration tests, robot tests, ...
• [ ] Includes documentation?
  • Documentation - Does the change contain explicit documentation additions outside direct code modifications (and comments)?
  • Examples: Update readme file, add feature readme file, link to documentation on an a separate Web page, ...

How This Was Tested

This routine was integrated into Q35 and verified bootable till EndOfDxe.

Integration Instructions

N/A