ref: e081ab2f41e4b3b4c5d53b9fe319bc4827a2564e drmdb/drmdoc d---------
drmdoc: update docs from upstream
drmdoc: stop accumulating content if indentation is missing

When indentation is missing, that means the docs for the prop are
finished. DRM docs often contain free-form paragraphs between prop docs.
drmdoc: sort props by name

This ensures the output order is deterministic.
drmdoc: use go/format to format generated files
drmdoc: new package