CodeQL Fixes - Second Pass

[makubacki]

Description

Makes changes to comply with alerts raised by CodeQL.

A prior pass with a subset of queries used here was already done so this is mostly addressing issues discovered by enabling a few new queries.

Most of the issues here fall into the following two categories:

1. Potential use of uninitialized pointer
2. Inconsistent integer width used in loop comparison

• [ ] Breaking change?
  • Will this change break pre-existing builds or functionality without action being taken? No - Should just be refactoring to address alerts

How This Was Tested

1. Verified CI build
2. Verified boot to EFI shell on QemuQ35Pkg

Integration Instructions

N/A

Signed-off-by: Michael Kubacki [email protected]