http: fix deprecation warning module ID

Mea culpa, I told @mmalecki wrong

lib/http.js

@@ -1590,7 +1590,7 @@ exports._connectionListener = connectionListener;
 
 function Client(port, host) {
   // TODO http.Client can be removed in v0.9. Until then leave this message.
-  util._deprecationWarning('http.Client', 'http.Client is a legacy interface' +
+  util._deprecationWarning('http', 'http.Client is a legacy interface' +
                 ' and will be removed in the near future. Do not use it.');
   host = host || 'localhost';
   port = port || 80;