Remove outdated references to ContextLoaderServlet

Issue: SPR-7725
(cherry picked from commit 69998e3)

spring-orm-hibernate4/src/main/java/org/springframework/orm/hibernate4/support/OpenSessionInViewFilter.java

@@ -63,9 +63,7 @@ import org.springframework.web.filter.OncePerRequestFilter;
  *
  * <p>Looks up the SessionFactory in Spring's root web application context.
  * Supports a "sessionFactoryBeanName" filter init-param in {@code web.xml};
- * the default bean name is "sessionFactory". Looks up the SessionFactory on each
- * request, to avoid initialization order issues (when using ContextLoaderServlet,
- * the root application context will get initialized <i>after</i> this filter).
+ * the default bean name is "sessionFactory".
  *
  * @author Juergen Hoeller
  * @since 3.1