drm/amd/amdgpu: psp program IH_RB_CTRL on sienna_cichlid

[Why]
IH_RB_CNTL is blocked by PSP so we need to ask psp to help config it.

[How]
Move psp ip block before ih, and use psp to program IH_RB_CNTL under sriov.

Reviewed-by: Chen, Horace <Horace.Chen@amd.com>
Signed-off-by: YuBiao Wang <YuBiao.Wang@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>