BUG/MINOR: mux-htx: Fix bad test on h1c flags in h1_recv_allowed()

A logical OR was used instead of a binary OR. Thanks to David Carlier to spot
and report this bug.
diff --git a/src/mux_h1.c b/src/mux_h1.c
index 87b5841..2e28d36 100644
--- a/src/mux_h1.c
+++ b/src/mux_h1.c
@@ -128,7 +128,7 @@
 static inline int h1_recv_allowed(const struct h1c *h1c)
 {
 	if (b_data(&h1c->ibuf) == 0 &&
-	    (h1c->flags & (H1C_F_CS_ERROR||H1C_F_CS_SHUTW) ||
+	    (h1c->flags & (H1C_F_CS_ERROR|H1C_F_CS_SHUTW) ||
 	     h1c->conn->flags & CO_FL_ERROR ||
 	     conn_xprt_read0_pending(h1c->conn)))
 		return 0;