Call SetShmBase() in init_rs

The ShmEventLoop rust test was using /dev/shm/aos and breaking out of
the sandbox. Fix that.

Change-Id: I14db8b500a03a66fef41399c4cea334ff79b217f
Signed-off-by: James Kuszmaul <james.kuszmaul@bluerivertech.com>
diff --git a/aos/events/shm_event_loop.h b/aos/events/shm_event_loop.h
index 7b7e68f..0e71f96 100644
--- a/aos/events/shm_event_loop.h
+++ b/aos/events/shm_event_loop.h
@@ -8,11 +8,11 @@
 #include "aos/events/epoll.h"
 #include "aos/events/event_loop.h"
 #include "aos/events/event_loop_generated.h"
+#include "aos/ipc_lib/shm_base.h"
 #include "aos/ipc_lib/signalfd.h"
 #include "aos/stl_mutex/stl_mutex.h"
 
 DECLARE_string(application_name);
-DECLARE_string(shm_base);
 
 namespace aos {
 namespace shm_event_loop_internal {