Refactor DRM presentation
Presentation doesn't have to go through DrmBackend and by moving DrmGpu::deleteBufferAfterPageflip into DrmBuffer some code can be simplified
Like !766 (merged), split out of !632 (closed)
Presentation doesn't have to go through DrmBackend and by moving DrmGpu::deleteBufferAfterPageflip into DrmBuffer some code can be simplified
Like !766 (merged), split out of !632 (closed)