Add RFC 5080 message authenticator support to the authenticator (RADIUS client) in core

[pmhausen]

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Is your feature request related to a problem? Please describe.

In #4306 we just added RFC 5080 message authenticator support to the FreeRADIUS plugin. It would be nice if the client implementation in core had the matching feature.

It's out of my league to implement this change in the core code. I have learned to find my way around most of the MVC based modules, but this file - no idea, sorry.

Describe the solution you'd like

A single boolean option to enable message authenticator in src/opnsense/mvc/app/library/OPNsense/Auth/Radius.php

Describe alternatives you've considered

None.

Additional context

https://forum.opnsense.org/index.php?topic=42094.0

Kind regards,
Patrick