Remove unused Cleanup() call

It was used to clean up shared memory.  We don't construct that anymore,
so remove the useless call.

Change-Id: I8087cef2afce184f66721a9995a63053fb278ec7
diff --git a/aos/aos_dump.cc b/aos/aos_dump.cc
index fe6cbd5..62fb5cb 100644
--- a/aos/aos_dump.cc
+++ b/aos/aos_dump.cc
@@ -115,6 +115,6 @@
   }
 
   event_loop.Run();
-  ::aos::Cleanup();
+
   return 0;
 }