Update Crosshatch SVN to 31
Bug: 153882927

Change-Id: I3e200890ab5cc65935d3f1b2576a9ee1a883207e
diff --git a/device.mk b/device.mk
index 221d5d9..37d7044 100644
--- a/device.mk
+++ b/device.mk
@@ -827,7 +827,7 @@
 
 # Increment the SVN for any official public releases
 PRODUCT_PROPERTY_OVERRIDES += \
-    ro.vendor.build.svn=30
+    ro.vendor.build.svn=31
 
 PRODUCT_PRODUCT_PROPERTIES += \
     ro.adb.secure=1