CI: generate ABI files if changed

[gmelikov]

So commit author can just download them as
artifacts and commit.

Example: https://github.com/gmelikov/zfs/actions/runs/1035256532

Signed-off-by: George Melikov [email protected]

Motivation and Context

Prepare everything for developer in CI.
Minor bonus - nearly identical build env = less unnecessary diff in files.

Description

Generate new ABI files on chekABI fail and present it as artifact, so developer can just download it and tar -xf abi_files.tar.

How Has This Been Tested?

Manual CI run, downloaded generated files and run make checkabi with them on fresh clone of repo.

Types of changes

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Performance enhancement (non-breaking change which improves efficiency)
• Code cleanup (non-breaking change which makes code smaller or more readable)
• Breaking change (fix or feature that would cause existing functionality to change)
• Library ABI change (libzfs, libzfs_core, libnvpair, libuutil and libzfsbootenv)
• Documentation (a change to man pages or other documentation)

[ghost]

This is a neat way of handling things! I do notice that the artifact is a .zip that contains a .tar, but at least on my mac the tar is extracted automatically anyway.

It would still be good to improve the portability of the *abi targets for use by downstream projects. I don't really want to have to push everything to github constantly. I do a lot of iterating locally and push to internally hosted git repos and CI systems before pushing to github. But at least this reduces the friction of contributions!