service: remove unused opts from newService() (unparam)
service: remove unused opts from newService() (unparam)

```
cli/command/service/client_test.go:75:41: `newService` - `opts` always receives `nil` (unparam)
func newService(id string, name string, opts ...func(*swarm.Service)) swarm.Service {
                                        ^
```

Signed-off-by: Sebastiaan van Stijn <64b2b6d12bfe4baae7dad3d018f8cbf6b0e7a044@gone.nl>

docker/cli,thaJeztah/cli,cpuguy83/cli,thaJeztah/cli,cpuguy83/cli,docker/cli