Add key symbols to the auxillary file

[Javagedes]

Description

Adds two additional fields to IMAGE_VALIDATION_DATA_HEADER, KeySymbolCount and OffsetToFirstKeySymbol and a new struct, KEY_SYMBOL which is a U32, U32 (Signature / Offset) pair.

Updates the aux gen to support adding key symbols via the config file by using the [[key]] config header.

This will allow a consumer of the auxillary file to define a set of key symbols that are necessary before performing any validation of an efi. The expectation is that the signature will allow the consumer to identify the purpose of the provided offset and act accordingly. The expectation is not that the signature will match the symbol name, but the purpose that the symbol is used for.

+--------------------------------------------+
+  IMAGE_VALIDATION_DATA_HEADER
+--------------------------------------------+
+  KEY_SYMBOL's
+--------------------------------------------+
+  IMAGE_VALIDATION_ENTRY_HEADER's
+--------------------------------------------+
+  Raw Data
+--------------------------------------------+

• [ ] 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

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Integration Instructions

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