unix: fix busy loop on unexpected tcp message

Don't start reading immediately after connecting. If the server sends a message
and the client hasn't called uv_read_start() yet, the event loop will busy loop
because the pending message keeps waking it up.

src/unix/stream.c

@@ -784,9 +784,6 @@ static void uv__stream_connect(uv_stream_t* stream) {
   if (error == EINPROGRESS)
     return;
 
-  if (error == 0)
-    uv__io_start(stream->loop, &stream->read_watcher);
-
   stream->connect_req = NULL;
   uv__req_unregister(stream->loop, req);