MINOR: mux-h1: Improve H1 traces by adding info about http parsers

Info about the request and the response parsers are now displayed in H1
traces for advanced and complete verbosity only. This should help debugging.

This patch may be backported as far as 2.4.
diff --git a/src/mux_h1.c b/src/mux_h1.c
index 6cb7ec8..3d5a24f 100644
--- a/src/mux_h1.c
+++ b/src/mux_h1.c
@@ -299,10 +299,19 @@
 	chunk_appendf(&trace_buf, " : [%c]", ((h1c->flags & H1C_F_IS_BACK) ? 'B' : 'F'));
 
 	/* Display request and response states if h1s is defined */
-	if (h1s)
+	if (h1s) {
 		chunk_appendf(&trace_buf, " [%s, %s]",
 			      h1m_state_str(h1s->req.state), h1m_state_str(h1s->res.state));
 
+		if (src->verbosity > H1_VERB_SIMPLE) {
+			chunk_appendf(&trace_buf, " - req=(.fl=0x%08x .curr_len=%lu .body_len=%lu)",
+				      h1s->req.flags, (unsigned long)h1s->req.curr_len, (unsigned long)h1s->req.body_len);
+			chunk_appendf(&trace_buf, "  res=(.fl=0x%08x .curr_len=%lu .body_len=%lu)",
+				      h1s->res.flags, (unsigned long)h1s->res.curr_len, (unsigned long)h1s->res.body_len);
+		}
+
+	}
+
 	if (src->verbosity == H1_VERB_CLEAN)
 		return;