mingw-w64-git: switch to asciidoctor and enable arm64 for it

[dennisameling]

While enabling clangarm64 support on GfW's
mingw-w64-asciidoctor-extensions package, we realized that the
extensions are likely not needed anymore, because the Git project
added its own Documentation/asciidoctor-extensions.rb back in 2017.

Let's switch to the MSYS2-maintaned mingw-w64-asciidoctor instead,
so we don't have to maintain our own package anymore.

Ref: #118
Ref: git/git@55d2d81

Let's also enable arm64 support while we're at it.

[dscho]

🎉

[dennisameling]

Ha, CI is failing with this error:

error: failed to commit transaction (conflicting files)
mingw-w64-x86_64-asciidoctor: /mingw64/bin/asciidoctor exists in filesystem
Errors occurred, no packages were upgraded.
==> ERROR: 'pacman' failed to install missing dependencies.
==> Missing dependencies:
  -> mingw-w64-x86_64-asciidoctor
==> ERROR: Could not resolve all dependencies.
Error: Process completed with exit code 8.

... which makes sense because the old asciidoctor-extensions also installed it like this in the filesystem. There's probably a way to address this efficiently. Any thoughts @dscho @rimrul?

[dscho]

There's probably a way to address this efficiently. Any thoughts @dscho @rimrul?

There' no PKGBUILD nor makepkg-mingw option I am aware of.

However, you could manually remove the offending package before invoking makepkg-mingw. Something along these lines:

test mingw-w64-git != '${{ matrix.directory }}' ||
test ! -d /var/lib/pacman/local/mingw-w64-*-asciidoctor-extensions-* ||
pacman -R --noconfirm mingw-w64-$MSYSTEM_CARCH-asciidoctor-extensions