[FIX] auth_ldap : add system parameter to disable referral chasing

To reproduce
============

- Using ldap server with Microsoft Active Directory
- Set up ldap authentication on Odoo
- Trying to log with a username/password from ldap on Odoo doesn't work

Purpose
=======

Because referral chasing is enabled by default, python-ldap ends up requesting
a completely different unrelated server.

Specification
=============

To solve the issue, a system parameter `disable_ldap_chase_ref` must be created
to have the possibility to disable referral chasing by setting its value to `True`.

opw-2724800

closes odoo/odoo#86436

Signed-off-by: Olivier Dony <odo@odoo.com>