drm/amdgpu: bypass RLC init under sriov for Tonga (v2)

RLC will go wrong in soft_reset under sriov

Workaroound: only need to init RLC csb, and skip RLC stop, reset, start
    this is because host-driver has already done full initialization on RLC

v2: squash in build fix

Signed-off-by: Tiecehng Zhou <Tiecheng.Zhou@amd.com>
Acked-by: Alex Deucher <alexander.deucher@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>