Add dummy function for xgmi function interface with psp
Signed-off-by: NShaoyun Liu <Shaoyun.Liu@amd.com>
Reviewed-by: NFelix Kuehling <Felix.Kuehling@amd.com>
Reviewed-by: NHuang Rui <ray.huang@amd.com>
Signed-off-by: NAlex Deucher <alexander.deucher@amd.com>