request #7501: Undefined variable: xml_file_path

This is a follow-up of commit #9afcd2f. Installation of Tuleap since
then was failing.

Change-Id: I8ca8145e5dbb7b037ffe980c8c9899a50ff578eb
Merge commit 'refs/changes/83/3083/2' of ssh://gerrit.tuleap.net:29418/tuleap into tuleap-stable-master

* ssh://gerrit.tuleap.net:29418/tuleap:
  request #7501: Undefined variable: xml_file_path

Change-Id: I556cb54c33be111fb99d9be9300f22135ba9f2d8
Tuleap 7.5.99.32

Change-Id: I16ca115291ff80fad0142ce60b693d1fbae3b039