Manifest for Android N IOT Preview 2 (NIG40)

Change-Id: Iae87131b95246f14f220e78e0ed90c8c93b4e36f
diff --git a/default.xml b/default.xml
index 2a31640..6fd31b5 100644
--- a/default.xml
+++ b/default.xml
@@ -4,7 +4,7 @@
   <remote  name="aosp"
            fetch=".."
            review="https://android-review.googlesource.com/" />
-  <default revision="n-iot-preview-2"
+  <default revision="refs/tags/android-n-iot-preview-2"
            remote="aosp"
            sync-j="4" />