drm/amdgpu/discovery: add HDP v5.2.1 into the IP discovery list

This patch is to add HDP v5.2.1 in the IP discovery list.

Signed-off-by: Xiaojian Du <Xiaojian.Du@amd.com>
Reviewed-by: Huang Rui <ray.huang@amd.com>
Reviewed-by: Alex Deucher <alexander.deucher@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>