Make empty sections DEBUG3, not DEBUG2.

If we know they're empty, we don't care to get told that
on every packet.

We'll take the chance with people who delete the sections, and
then complain that they're not being processed.

src/main/modules.c

@@ -752,7 +752,7 @@ rlm_rcode_t indexed_modcall(rlm_components_t comp, int idx, REQUEST *request)
 
 	if (idx == 0) {
 		list = server->mc[comp];
-		if (!list) RWDEBUG2("Empty %s section.  Using default return values.", section_type_value[comp].section);
+		if (!list) RWDEBUG3("Empty %s section.  Using default return values.", section_type_value[comp].section);
 
 	} else {
 		indexed_modcallable *this;