Initialize mainloop events earlier, since other stuff may run them.

Fixes a stem test failure; bugfix on c7ce6b9821. Bug
not in any released Tor.

src/core/mainloop/mainloop.c

@@ -2675,7 +2675,7 @@ dns_servers_relaunch_checks(void)
 }
 
 /** Initialize some mainloop_event_t objects that we require. */
-STATIC void
+void
 initialize_mainloop_events(void)
 {
   if (!schedule_active_linked_connections_event) {