ssh: Partial blocklistd rename

[emaste]

Summary

The upstream project was renamed blocklistd. Chase the rename in ssh to go along with an upcoming vendor update, and document UseBlacklist as the backwards-compatibility alias.

(This has been sitting in my WIP tree for 1.5 years.)

[emaste]

Correct rebase errors

crypto/openssh/servconf.h

256

extra blank line presumably from rebasing, will remove

[emaste]

crypto/openssh/sshd_config.5

2016

This one will come with the rename itself in a future commit

[jlduran]

While this is perfect, I fear this could make automated changes more difficult.
This is our current diff once the latest changes from upstream are pulled in:
https://github.com/jlduran/freebsd-src/pull/104
The shell script in the GitHub pull request is very straightforward. Perhaps we could include it as part of a FreeBSD-upgrade guide.
The main problem with this change is that it is an API change (OK for 15, but not for the rest).

[jlduran]

Also missing:

• libexec/ftpd/blacklist_client.hlibexec/ftpd/blacklist_client.h
• libexec/ftpd/ftpd.c

[jlduran]

Sorry, I just realized this is just for openssh.

[jlduran]

Sorry for the confusion. This is a step forward in the naming transition. Thank you!

[jlduran]

crypto/openssh/auth-pam.c

940

Somewhat related, passing NULL as the first parameter does nothing (ssh_packet_connection_is_on_socket(NULL);). Given BLOCKLIST_BAD_USER has been implemented upstream.