dialog: if sending BYE fails at timeout, unref dialog

- destroy dialog structures

(cherry picked from commit e39a90e11bfed2b4445c37db1532488aa9e3e725)
(cherry picked from commit 12a0a927aa3ad6dfbb18ab3fcf1927bf51098925)

modules/dialog/dlg_handlers.c

@@ -1353,7 +1353,8 @@ void dlg_ontimeout(struct dlg_tl *tl)
 
 		if(dlg->iflags&DLG_IFLAG_TIMEOUTBYE)
 		{
-			dlg_bye_all(dlg, NULL);
+			if(dlg_bye_all(dlg, NULL)<0)
+				dlg_unref(dlg, 1);
 			/* run event route for end of dlg */
 			dlg_run_event_route(dlg, NULL, dlg->state, DLG_STATE_DELETED);
 			dlg_unref(dlg, 1);