AMDGPU Linux 4.21 Changes Queued With FreeSync, DC ABM, KFD Compute For Vega12/Polaris12

On Friday AMD's Alex Deucher sent in the latest batch of feature to work DRM-Next ahead of the Linux 4.21 cycle. This mostly included AMDGPU/AMDKFD driver updates but also a lone Radeon DRM driver fix to avoid a possible 32-bit overflow and also DRM scheduler and TTM memory management fixes...