drm/amdgpu/: drm/amdgpu: Register the new sdma function pointers for sdma_v5_0

Register stop/start/soft_reset queue functions for SDMA IP versions v5.0.

Suggested-by: Alex Deucher <alexander.deucher@amd.com>
Signed-off-by: Jesse Zhang <jesse.zhang@amd.com>
Reviewed-by: Alex Deucher <alexander.deucher@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>