init.rc: Add socket for adbd

Change-Id: Ic97fd464440ff4a29fc9da7ad15949ac5215ade3
diff --git a/rootdir/init.rc b/rootdir/init.rc
index 8f692ac..313a98e 100644
--- a/rootdir/init.rc
+++ b/rootdir/init.rc
@@ -358,6 +358,7 @@
 # adbd is controlled via property triggers in init.<platform>.usb.rc
 service adbd /sbin/adbd
     class core
+    socket adbd stream 660 system system
     disabled
 
 # adbd on at boot in emulator