drm/amdgpu: add rlc TOC header file for soc21 (v2)

Add RLC autoload TOC header file for soc21 ASIC.

v2: squash in updates

Signed-off-by: Likun Gao <Likun.Gao@amd.com>
Reviewed-by: Hawking Zhang <Hawking.Zhang@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>