Add file contexts for OnDevicePersonalization.

Test: build
Change-Id: I7fc206f06ca1dad52772211abef50407437a79dc
diff --git a/apex/Android.bp b/apex/Android.bp
index b85b1f5..5d61303 100644
--- a/apex/Android.bp
+++ b/apex/Android.bp
@@ -263,3 +263,10 @@
     "com.android.car.framework-file_contexts",
   ],
 }
+
+filegroup {
+  name: "com.android.ondevicepersonalization-file_contexts",
+  srcs: [
+    "com.android.ondevicepersonalization-file_contexts",
+  ],
+}