Fix test

Author: smalyshev

ext/spl/tests/bug54291.phpt

@@ -5,7 +5,7 @@ Bug #54291 (Crash iterating DirectoryIterator for dir name starting with \0)
 $dir = new DirectoryIterator("\x00/abc");
 $dir->isFile();
 --EXPECTF--
-Fatal error: Uncaught UnexpectedValueException: Failed to open directory "" in %s:%d
+Fatal error: Uncaught UnexpectedValueException: DirectoryIterator::__construct() expects parameter 1 to be a valid path, string given in %s:%d
 Stack trace:
 #0 %s(%d): DirectoryIterator->__construct('\x00/abc')
 #1 {main}