AMD Navi
This is initial Navi10 support.
Major deltas from the driver point of view:
- The GS stage is used instead of VS. GS is now a merged ES-GS-VS and is more efficient. In this mode, API shaders VS, TES, and GS are said to be compiled as NGG.
- Transform feedback is completely emulated with the help of GDS ordered atomics. Transform feedback queries have to be emulated too. (it might still be faster than the previous hw)
It works pretty well, but more improvements will be made.