pulse-server: skip objects being created

Skip iterating over objects that still have pending updates.
Make sure we have all info and properties before we process
objects.

Fixes #376

src/modules/module-protocol-pulse/manager.h

@@ -82,6 +82,7 @@ struct pw_manager_object {
 	int changed;
 	void *info;
 	struct spa_list param_list;
+	unsigned int creating:1;
 };
 
 struct pw_manager *pw_manager_new(struct pw_core *core);