MINOR: task/stream: tasks related to a stream must be init by the caller.

The task_wakeup was called on stream_new, but the task/stream
wasn't fully initialized yet. The task_wakeup must be called
explicitly by the caller once the task/stream is initialized.
diff --git a/src/session.c b/src/session.c
index 34250eb..46b9f67 100644
--- a/src/session.c
+++ b/src/session.c
@@ -276,6 +276,7 @@
 	strm->target         = sess->listener->default_target;
 	strm->req.analysers |= sess->listener->analysers;
 
+	task_wakeup(t, TASK_WOKEN_INIT);
 	return 1;
 
  out_free_task:
@@ -446,6 +447,7 @@
 	strm->req.analysers |= sess->listener->analysers;
 	conn->flags &= ~CO_FL_INIT_DATA;
 
+	task_wakeup(task, TASK_WOKEN_INIT);
 	return 0;
 
  fail: