drm/amdgpu: centrally calls the .ras_fini function of all ras blocks

centrally calls the .ras_fini function of all ras blocks.

Signed-off-by: yipechai <YiPeng.Chai@amd.com>
Reviewed-by: Tao Zhou <tao.zhou1@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>