MSYS2 package

[pedrolcl]

This is to be done after the release.

https://www.msys2.org/dev/new-package/

[pedrolcl]

msys2/MINGW-packages#27799

[pedrolcl]

I was willing to make the package for v4.0.0 but @lazka has beaten me. Thanks!

This ticket remains open to remember triggering an update after the upcoming release v4.0.1 and...

• the patch will not apply because da56630 so remove it
• build and install the sources twice, shared and static, like the fluidsynth package