drm/amdgpu: Fix compile error.

Seems I forgot to add this to the relevant commit
when submitting.

Signed-off-by: Andrey Grodzovsky <andrey.grodzovsky@amd.com>
Reported-by: kernel test robot <lkp@intel.com>
Reviewed-by: Christian König <christian.koenig@amd.com>
Signed-off-by: Christian König <christian.koenig@amd.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20220210031724.440943-1-andrey.grodzovsky@amd.com