gen_headers/meson_*.in not included in tarball
We have added formerly-WIP meson.build and some related files to distribution, but not gen_headers/meson_*.in files. That results in having meson based build system in distribution, but in broken form.
Applies on top of #42114.
We have added formerly-WIP meson.build and some related files to distribution, but not gen_headers/meson_*.in files. That results in having meson based build system in distribution, but in broken form.