default.xml: cm: Update to 6.0.1_r52

Change-Id: Ibc1382307d029c7673eaa1a7c466846c6276389d
Ticket: CYNGNOS-3020
diff --git a/default.xml b/default.xml
index 85dc4b5..7948471 100644
--- a/default.xml
+++ b/default.xml
@@ -4,7 +4,7 @@
   <remote  name="aosp"
            fetch="https://android.googlesource.com"
            review="android-review.googlesource.com"
-           revision="refs/tags/android-6.0.1_r46" />
+           revision="refs/tags/android-6.0.1_r52" />
 
   <remote  name="github"
            fetch=".."