Let SocketClient users write binary data to clients.

This is a dependency for the DNS proxy CLs.

This CL also adds a new socket for the netd process to inherit which
is owned by the inet group.  (so only apps with the INTERNET
permission can use the DNS proxy...)

Change-Id: Ic3475c697913ba85805b4e49801b65e7a1d59289
diff --git a/rootdir/init.rc b/rootdir/init.rc
index 6bc2e5d..79baf9a 100644
--- a/rootdir/init.rc
+++ b/rootdir/init.rc
@@ -309,6 +309,7 @@
 
 service netd /system/bin/netd
     socket netd stream 0660 root system
+    socket dnsproxyd stream 0660 root inet
 
 service debuggerd /system/bin/debuggerd