Permit the %l and %L escapes in the Include directive.

[rpigott]

These patches were originally submitted on-list in [1] and [2], but it I am resubmitting them here.

The goal is to enable including per (local) host configuration for ssh.

[1] https://lists.mindrot.org/pipermail/openssh-unix-dev/2023-June/040788.html

[2] https://lists.mindrot.org/pipermail/openssh-unix-dev/2024-July/041437.html

[djmdjm]

See https://bugzilla.mindrot.org/show_bug.cgi?id=3246 for a more comprehensive patch that allows most of the common %-characters as well as environment variables.

[rpigott]

Hi @djmdjm, that patch LGTM. I tried it and it works as expected. Happy to close this PR if that can be merged instead.

[rpigott]

Closing in favor of @djmdjm's patch.