drm/amdgpu: implement HDP functions for UVD v2

Flush and invalidate the HDP caches.

v2: fix typo in comment

Signed-off-by: Christian König <christian.koenig@amd.com>
Reviewed-by: Alex Deucher <alexander.deucher@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
3 files changed