security/openvpn: security update to 2.7.2
(also includes OpenSSL 4.0 support, improved error messages and others)
Changelog: https://github.com/OpenVPN/openvpn/blob/v2.7.2/Changes.rst
Security: 549313db-3e93-11f1-8d38-7fbbe0285610
Security: CVE-2026-35058
Security: CVE-2026-40215
MFH: 2026Q2
PR: 294714
(cherry picked from commit 1c4a6954619f73bf001ec6799699282ecf61de0c)