drm/amdgpu: add new helper for in kernel allocations

We often allocate, pin and map things at the same time in the kernel.

Signed-off-by: Christian König <christian.koenig@amd.com>
Reviewed-by: Chunming Zhou <david1.zhou@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
2 files changed