fix gatekeper_device_test

ASSERT_LT parameters were in the wrong order

Change-Id: I7c5a5eb4a44e0dabd21d5d2e7b00d8bff3e774c7
diff --git a/tests/gatekeeper_device_test.cpp b/tests/gatekeeper_device_test.cpp
index d2283ec..9c4c82f 100644
--- a/tests/gatekeeper_device_test.cpp
+++ b/tests/gatekeeper_device_test.cpp
@@ -195,7 +195,7 @@
                 password_payload, password_len, &auth_token, &auth_token_len,
                 &should_reenroll);
         // shoudln't be a timeout
-        ASSERT_LT(0, ret);
+        ASSERT_LT(ret, 0);
     }
 }