Enable ppc64le

Previously closed discussion: https://github.com/actions/setup-python/issues/613

Description:
Build python binaries for ppc64le and enable support for ppc64le in this repo.

Justification:
We recently launched GitHub Actions so open source projects can use runners on our Power and Z hardware. At this point, we are onboarding projects to use our GitHub actions service. Here is a blog post about our announcement and our official GitHub repo is located here.

This would greatly benefit a lot of open source communities to have the python action runner be supported on ppc64le. My goal is to eliminate inconsistencies with ppc64le and have parity with other archs (like with our newly released github actions).

Are you willing to submit a PR?
Yes absolutely. We can assist with any development, testing, and other needs if this feature request can be included in a roadmap.

Empieza leyendo la discusión cerrada anteriormente en actions/setup-python#613 y, después, localiza los puntos de entrada de build y release de este repositorio; el issue no menciona archivos ni tests. Se considera terminado cuando se compilan binarios de Python para ppc64le y la action admite esa arquitectura, con cobertura para la nueva ruta.