feat(FFmpeg): compile libva dependency

[cgutman]

Description

This PR builds libva 2.23 which is necessary to fix LizardByte/Sunshine#4314. It contains the changes from #535 plus fixes for theFreeBSD build errors.

To summarize why the approaches in #535 didn't work:

• The NFS sync method cannot be used with libva because autom4te requires file locks to run which are not supported by our NFS mount (I assume you found this out and that's why you tried switching to sshfs/rsync)
• Switching away from NFS to rsync means that syncing is no longer implicitly happening because you're not mounting the host filesystem directly into the VM anymore. Handling that requires an explicit step to sync the VM's build artifacts back to the host.
• The reason for the sh: -C: not found error was because the change to GITHUB_ENV was no longer being implicitly synced back to the host, so MAKE_CMD is undefined and you end up trying to run -C build .... By changing the order of the steps to set these variables before starting the VM, they are correctly propagated into the VM.

Screenshot

Issues Fixed or Closed

• Closes feat(FFmpeg): compile libva dependency #535

Roadmap Issues

Type of Change

• feat: New feature (non-breaking change which adds functionality)
• fix: Bug fix (non-breaking change which fixes an issue)
• docs: Documentation only changes
• style: Changes that do not affect the meaning of the code (white-space, formatting, missing semicolons, etc.)
• refactor: Code change that neither fixes a bug nor adds a feature
• perf: Code change that improves performance
• test: Adding missing tests or correcting existing tests
• build: Changes that affect the build system or external dependencies
• ci: Changes to CI configuration files and scripts
• chore: Other changes that don't modify src or test files
• revert: Reverts a previous commit
• BREAKING CHANGE: Introduces a breaking change (can be combined with any type above)

Checklist

• Code follows the style guidelines of this project
• Code has been self-reviewed
• Code has been commented, particularly in hard-to-understand areas
• Code docstring/documentation-blocks for new or existing methods/components have been added or updated
• Unit tests have been added or updated for any new or modified functionality

AI Usage

• None: No AI tools were used in creating this PR
• Light: AI provided minor assistance (formatting, simple suggestions)
• Moderate: AI helped with code generation or debugging specific parts
• Heavy: AI generated most or all of the code changes

[sonarqubecloud]

Quality Gate passed

Issues
0 New issues
0 Accepted issues

Measures
0 Security Hotspots
0.0% Coverage on New Code
0.0% Duplication on New Code

See analysis details on SonarQube Cloud