drm/amdgpu: move context switch handling into common code v2

It was a source of bugs to repeat that in each IP version.

v2: rename parameter

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>
12 files changed