ssh: default X11Forwarding to no, following upstream

[emaste]

Summary

Administrators can enable it if required.

[emaste]

rebase

[bz]

Does this require an UPDATING entry?

[emaste]

Does this require an UPDATING entry?

Good point, it does. I will stage that locally.

[emaste]

20230206:
        sshd now defaults to X11Forwarding disabled, following upstream.
        Administrators who wish to have X11Forwarding enabled should add
        `X11Forwarding yes` to /etc/ssh/sshd_config.