cm: android-7.1.1_r4 -> android-7.1.1_r6

Change-Id: Id1910bbf180fec6692307b7d09eec432ae0d30ca
diff --git a/default.xml b/default.xml
index c5c5d03..2093022 100644
--- a/default.xml
+++ b/default.xml
@@ -11,7 +11,7 @@
   <remote  name="aosp"
            fetch="https://android.googlesource.com"
            review="android-review.googlesource.com"
-           revision="refs/tags/android-7.1.1_r4" />
+           revision="refs/tags/android-7.1.1_r6" />
 
   <default revision="refs/heads/cm-14.1"
            remote="github"