Update neutral <-> ddi conversion functions involving types with flex-array members

[abeltrano]

Type

• Bug fix
• Feature addition
• Feature update
• Breaking change
• Non-functional change
• Documentation
• Infrastructure

Goals

Ensure the neutral <-> ddi conversion functions involving DDI types with flexible array member (FAM) types can be converted correctly.

Technical Details

• Update conversion functions with FAMs to use flextype_wrapper.
• Add constraint for flextype_wrapper::element_type to not be an array type.

Test Results

All unit tests pass on both Linux and Windows.

Reviewer Focus

None

Future Work

• Unit tests for each conversion function need to be added.
• Some of the conversion functions that are not needed now were left unimplemented. These will need to be completed at some point.

Checklist

• Build target all compiles cleanly.
• clang-format and clang-tidy deltas produced no new output.
• Newly added functions include doxygen-style comment block.