core.js: bindWithSignature is synchronous.

Change-Id: I4c9b26b988aee0c48be762c63e799a06ca392b61
diff --git a/src/rpc/client.js b/src/rpc/client.js
index 9048580..487c91b 100644
--- a/src/rpc/client.js
+++ b/src/rpc/client.js
@@ -453,12 +453,10 @@
  * @param {string} name The vanadium name of the service to bind to.
  * @param {module:vanadium.vdl.signature.Interface} signature The service
  * signature of a vanadium service.
- * @param {module:vanadium.rpc~Client~bindToCb} [cb] If given, this function
- * will be called on completion of the bind.
- * @return {Promise<object>} Promise that resolves to the stub object containing
+ * @return {object} Object The stub object containing
  * the exported methods of the remote service.
  */
-Client.prototype.bindWithSignature = function(name, signature, cb) {
+Client.prototype.bindWithSignature = function(name, signature) {
   var client = this;
   var boundObject = {};