Add Doxygen support

[abeltrano]

The Doxygen Action is invalid and has never succeeded as there is no Doxyfile defined for this project, as evidenced by the action error:

Run doxygen
error: Doxyfile not found and no input file specified!

It seems this was copied from the ebpf-for-windows repository as there are direct references to it:

    - name: Clone docs
      run: |
        git config --global user.email 'ebpf-for-windows@users.noreply.github.com'
        git config --global user.name 'Github Action'
        git clone --branch gh-pages https://github.com/microsoft/ebpf-for-windows.git docs/html

    - name: Update docs
      run: |
        doxygen
        cd docs/html
        git add .
        if [ -n "$(git status --porcelain)" ]; then
        git commit -s -m "Updated documentation"
        git remote set-url origin https://x-access-token:${{ secrets.GITHUB_TOKEN }}@github.com/microsoft/ebpf-for-windows.git
        git push
        fi

Doxygen support should be added such that the action succeeds.

[shankarseal]

Doxygen should be supported for this repo and a doxyfile should be introduced.

[shankarseal]

@abeltrano - can you please update the issue?

[abeltrano]

@shankarseal Updated to reflect Doxygen support should be added.