Fix CLANG build errors

[kuqin12]

Preface

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to submitting the pull request. In particular,
pull request guidelines.

Description

When building with CLANG/CLANGPDB, the compiler will generate errors for where the variable could be used without being initialized.

This change is added to mitigate such errors and pave way to build ARM platforms on Windows system.

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

• 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 was tested on QEMU SBSA platform and verified bootable to UEFI Shell.

Integration Instructions

N/A

[codecov-commenter]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 36.12%. Comparing base (7361a30) to head (31c00ac).

❗ Current head 31c00ac differs from pull request most recent head bd9992d. Consider uploading reports for the commit bd9992d to get more accurate results

Additional details and impacted files

@@           Coverage Diff           @@
##             main     #345   +/-   ##
=======================================
  Coverage   36.12%   36.12%           
=======================================
  Files          31       31           
  Lines        6229     6229           
  Branches      449      449           
=======================================
  Hits         2250     2250           
  Misses       3977     3977           
  Partials        2        2           

Flag	Coverage Δ
Linux	27.39% <ø> (ø)

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