Immediately return ErrTimeout if deadline is already reached.

[iv-menshenin]

I found this while developing unit tests for my application.

If we call DoDeadline without first checking that the deadline has expired, then we don't get the expected behavior of returning ErrTimeout.

The implementation (c *pipelineConnClient) of DoDeadline already contains the necessary check

	if req.timeout < 0 {
		return ErrTimeout
	}

I also added it for

• Client
• HostClient

[erikdubbelboer]

Thanks!