AMD Renoir APUs Bringing "DCN 2.1" Display Engine

Raven Ridge APUs brought the DCN 1.0 "Display Core Next" engine, Navi GPUs upped that to a DCN 2.0 implementation for the display engine, and now the Renoir APUs are ushering in DCN 2.1. This is a bit interesting particularly with Renoir being a Vega-based GPU and not Navi as one would have hoped prior to the Vega confirmation in the earlier patches...