[*] MO : Remove calls to isRegisteredInHook in crossselling and productscategory

modules/crossselling/upgrade/install-0.8.php

@@ -0,0 +1,11 @@
+<?php
+
+if (!defined('_PS_VERSION_'))
+	exit;
+
+function upgrade_module_0_8($object)
+{
+	if (!$object->isRegisteredInHook('header'))
+		return $object->registerHook('header');
+	return true;
+}