Add support for Open Quantum Safe provider

[RAYs3T]

Would it be possible to add support for OQS-Provider when compiling with openssl?

https://github.com/open-quantum-safe/oqs-provider

[catatsuy]

Currently, nginx-build only supports OpenSSL and LibreSSL.

However, since nginx-build does not verify the downloaded binaries, you can replace the OpenSSL source code with another implementation and build it. This is a kind of workaround.

There are also people who want to use other SSL libraries like BoringSSL. I will think about how to handle this properly. @RAYs3T