Bug 4086255 drmserver process needs system group

Change-Id: If9a325b9e716abe00f3ad6f20b012861308abd2d
diff --git a/rootdir/init.rc b/rootdir/init.rc
index 6cdf433..7f5a38f 100644
--- a/rootdir/init.rc
+++ b/rootdir/init.rc
@@ -401,7 +401,7 @@
 service drm /system/bin/drmserver
     class main
     user drm
-    group inet
+    group inet system
 
 service media /system/bin/mediaserver
     class main