[php] Fix director upcall check

This resolves an issue uncovered by adding a _runme.php for testcase
director_alternating.

Examples/test-suite/php/director_alternating_runme.php

@@ -0,0 +1,11 @@
+<?php
+
+require "tests.php";
+
+check::functions(array('getBar','idFromGetBar'));
+check::classes(array('Foo','Bar','Baz','director_alternating'));
+// No new vars
+check::globals(array());
+
+$id = director_alternating::getBar()->id();
+check::equal($id, director_alternating::idFromGetBar(), "idFromGetBar() failed");