Display closed UDP sockets on 'ss -ul'

This patch emulates 'netstat -ul' behavior, showing 'closed'
(state 07) UDP sockets when ss is called with '-ul' options.
Although dirty, this seems like the least invasive way to fix
it and shouldn't really break anything.
Signed-off-by: Petr Šabata <contyk@redhat.com>

misc/ss.c

@@ -2568,7 +2568,7 @@ int main(int argc, char *argv[])
 			current_filter.states = SS_ALL;
 			break;
 		case 'l':
-			current_filter.states = (1<<SS_LISTEN);
+			current_filter.states = (1<<SS_LISTEN) | (1<<SS_CLOSE);
 			break;
 		case '4':
 			preferred_family = AF_INET;