modules_k/dialog: Reduce log verbosity for list traversal of

expired dialogs.

- Change logging of start/previous/next pointers from WARN to DBG
  when traversing the list of expired dialogs.
(cherry picked from commit a5f03adcad92993e170be1d2a5dbb879b4777347)

modules_k/dialog/dlg_timer.c

@@ -237,18 +237,18 @@ static inline struct dlg_tl* get_expired_dlgs(unsigned int time)
 
 	end = &d_timer->first;
 	tl = d_timer->first.next;
-	LM_WARN("start with tl=%p tl->prev=%p tl->next=%p (%d) at %d "
+	LM_DBG("start with tl=%p tl->prev=%p tl->next=%p (%d) at %d "
 		"and end with end=%p end->prev=%p end->next=%p\n",
 		tl,tl->prev,tl->next,tl->timeout,time,
 		end,end->prev,end->next);
 	while( tl!=end && tl->timeout <= time) {
-		LM_WARN("getting tl=%p tl->prev=%p tl->next=%p with %d\n",
+		LM_DBG("getting tl=%p tl->prev=%p tl->next=%p with %d\n",
 			tl,tl->prev,tl->next,tl->timeout);
 		tl->prev = 0;
 		tl->timeout = 0;
 		tl=tl->next;
 	}
-	LM_WARN("end with tl=%p tl->prev=%p tl->next=%p and d_timer->first.next->prev=%p\n",
+	LM_DBG("end with tl=%p tl->prev=%p tl->next=%p and d_timer->first.next->prev=%p\n",
 		tl,tl->prev,tl->next,d_timer->first.next->prev);
 
 	if (tl==end && d_timer->first.next->prev) {