Detach thread before returning from android_main()

Change-Id: I593e94e90971b6be681de48dce74f7df2293c10e

sal/android/lo-bootstrap.c

@@ -2009,6 +2009,7 @@ android_main(struct android_app* state)
     }
 
     lo_main(lo_main_argc, lo_main_argv);
+    nRet = (*(*state->activity->vm)->DetachCurrentThread)(state->activity->vm);
     fprintf (stderr, "exit android_main\n");
 }