Drop libvarlink-util from package set

[dustymabe]

This was originally added for podman-remote functionality but the podman team ripped out varlink code in v3. We should be safe to remove it but there may be some users using it for other things. I feel like if there was ever an opportunity for us to actually remove a package, this would be it.

• the current definition

[jlebon]

Notably, this removes /usr/bin/varlink.

[travier]

I don't see a lot of activity in https://github.com/varlink/ and I don't know of major projects using it anymore.
If nothing uses it anymore in our default installation then it should be safe to remove. It can still be overlayed as needed for those that require it.

[dustymabe]

We discussed this in the community meeting today.

12:58:29    dustymabe | #agreed We don't know of any other common uses of
                      | libvarlink-utils on FCOS right now. We'll try removing it
                      | from `next` and send an email about it to the list to see
                      | if that gives us any new information. After a period of
                      | time with no issues we'll promote that to `testing` and
                      | `stable`.

[dustymabe]

At this point we should:

• send an email to the mailing lists notifying of the change
• drop it from any branches other than testing-devel, testing, and stable.
• wait some time and then drop it from the rest

[gursewak1997]

Draft email: Open to feedback

Subject: Fedora CoreOS dropping libvarlink-utils from base OSTree

We have decided to remove varlink (provided by the libvarlink-utils package) from Fedora CoreOS. Podman was the primary consumer of this package and the use of it was removed in Podman v3.0 and later [1]. At the moment, we are not aware of any other consumers of libvarlink-utils on FCOS.

The package will initially be removed from the next stream. It will be followed by testing and stable after it has been removed from next for at least a month.

The Fedora CoreOS Team

[1] https://podman.io/blogs/2020/08/01/deprecate-and-remove-varlink-notice.html#podman-api-v10-deprecation-and-removal-notice

[dustymabe]

The fix for this went into next stream release 36.20220410.1.1. Please try out the new release and report issues.

[dustymabe]

Let's drop it from the other branches any time after 05/12/2022.

[dustymabe]

The fix for this went into testing stream release 36.20220505.2.0. Please try out the new release and report issues.

[dustymabe]

The fix for this went into stable stream release 36.20220505.3.2.