drm/amdgpu:change VEGA booting with firmware loaded by PSP

With PSP firmware loading, TMR mc address is supposed to be used.

Signed-off-by: James Zhu <James.Zhu@amd.com>
Acked-by: Huang Rui <ray.huang@amd.com>
Reviewed-by: Alex Deucher <alexander.deucher@amd.com>
Signed-off-by: Feifei Xu <Feifei.Xu@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>