drm/amdgpu: add user fence context map v2

This is a prerequisite for the GPU scheduler to make the order
of submission independent from the order of execution.

v2: properly implement the locking

Signed-off-by: Christian König <christian.koenig@amd.com>
Reviewed-by: Jammy Zhou <Jammy.Zhou@amd.com>
Reviewed-by: Chunming Zhou <david1.zhou@amd.com>
4 files changed