drm/amdgpu: add mmhub v3_0_1 ip block

This adds mmhub v3_0_1 ip block support

v2: rebase (Alex)

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