MEDIUM: mux-h1: Wait for connection establishment before consuming channel's data

When a server is down, the channel's data must not be consumed. This is
required to allow redispatch and connection retry. So now, we wait for
the connection to be marked as connected, with the flag CO_FL_CONNECTED,
before starting to consume channel's data. In the mux, this event is
tracked with the flag H1C_F_CS_WAIT_CONN.
diff --git a/src/stream.c b/src/stream.c
index 515dc0d..ae8318d 100644
--- a/src/stream.c
+++ b/src/stream.c
@@ -666,11 +666,8 @@
 		return 1;
 	}
 
-	/* FIXME: Add CF_WROTE_DATA because data was already move in the mux in
-	 * h1. Without it, the SI remains in SI_ST_CON state.
-	 */
 	/* we need to wait a bit more if there was no activity either */
-	if (!(req->flags & (CF_WROTE_DATA|CF_WRITE_ACTIVITY)))
+	if (!(req->flags & CF_WRITE_ACTIVITY))
 		return 1;
 
 	/* OK, this means that a connection succeeded. The caller will be