[incrementa;] set mode and encryption for /data/incremental

To be consistent with /data/app.

Test: boots
BUG: 137855266
Change-Id: I8aa549155367edfad158924bcf7892ac7bb76f16
diff --git a/rootdir/init.rc b/rootdir/init.rc
index 803d44a..ae25b88 100644
--- a/rootdir/init.rc
+++ b/rootdir/init.rc
@@ -689,7 +689,7 @@
     mkdir /data/rollback-observer 0700 system system encryption=DeleteIfNecessary
 
     # Create root dir for Incremental Service
-    mkdir /data/incremental 0770 system system encryption=None
+    mkdir /data/incremental 0771 system system encryption=Require
 
     # Wait for apexd to finish activating APEXes before starting more processes.
     wait_for_prop apexd.status ready