xr: add AMD DSC PPS debugfs diagnostic carry

[Jess Sullivan (Jesssullivan)]

Summary

• add a local Honey lab diagnostic carry patch exposing the cached AMD DSC PPS through connector debugfs
• wire the new carry patch into kernel-xr.spec, xr/patches/series, and build/release summaries
• add check-rpm-patch-wiring.sh and call it from carry/build paths plus CI before RPM builds

Boundaries

This is observability for Bigscreen Beyond / Honey black-screen proof work. It does not retrain links, reprogram DSC, mutate stream state, or claim upstream-ready behavior.

Validation

• ruby -ryaml -e 'ARGV.each { |path| YAML.load_file(path); puts path }' .github/workflows/build-kernel.yml
• bash -n xr/scripts/check-rpm-patch-wiring.sh xr/scripts/build-rpm.sh xr/scripts/check-kernel-carry.sh
• bash xr/scripts/check-rpm-patch-wiring.sh
• xr/scripts/check-kernel-carry.sh --kernel-version 6.19.5
• git diff --check

[Jess Sullivan (Jesssullivan)]

Validation refreshed for the Honey display-proof lane.

Local repo: /Users/jess/git/linux-xr-fast
Branch: codex/amdgpu-dsc-pps-debugfs
Head: 7455fa3d2d299

Passed:

• YAML parse for .github/workflows/build-kernel.yml
• bash -n xr/scripts/check-rpm-patch-wiring.sh xr/scripts/build-rpm.sh xr/scripts/check-kernel-carry.sh
• bash xr/scripts/check-rpm-patch-wiring.sh
• xr/scripts/check-kernel-carry.sh --kernel-version 6.19.5
• xr/scripts/check-kernel-carry.sh --kernel-version 6.19.14
• git diff --check

I marked this ready for review. Scope remains read-only diagnostic observability for Honey/Bigscreen PPS evidence; it does not retrain links, change stream state, or claim a visual first-frame fix.

[Jess Sullivan (Jesssullivan)]

Post-merge follow-up:

• Merge commit: dbfcd3938a2f3.
• Post-merge Determinate CI is green: https://github.com/tinyland-inc/linux-xr/actions/runs/25710732827
• Dispatched artifact-only generic RPM diagnostic build for 6.19.5-xr12: https://github.com/tinyland-inc/linux-xr/actions/runs/25710987473
• Current state: generic job is in Build RPMs; RT matrix entry is queued only because the workflow matrix still creates it and should skip under variant=generic.

This is read-only DSC PPS observability. It is not a release tag and not a visual fix claim.