naughty.dbus: Make this actually work

Apparently I still had an old naughty.lua laying around in build/lib and thus
this new code wasn't actually tested. It's a miracle that it works so well
besides this.

Signed-off-by: Uli Schlachter <psychon@znc.in>

lib/naughty/dbus.lua.in

@@ -25,7 +25,7 @@ local tins = table.insert
 local naughty = require("naughty.core")
 
 --- Notification library, dbus bindings
-local dbus = {}
+local dbus = { config = {} }
 
 -- DBUS Notification constants
 local urgency = {