Manifest for Android O IOT Preview 6 (4475743)

Change-Id: I6a4105e7c2bd6729ecbaf430d03f9510af11aa44
diff --git a/default.xml b/default.xml
index c814f00..2ac6325 100644
--- a/default.xml
+++ b/default.xml
@@ -4,7 +4,7 @@
   <remote  name="aosp"
            fetch=".."
            review="https://android-review.googlesource.com/" />
-  <default revision="o-mr1-iot-preview-6"
+  <default revision="refs/tags/android-o-mr1-iot-preview-6"
            remote="aosp"
            sync-j="4" />