Makefile.m32: support more options [ci skip]

Makefile.m32: support more options [ci skip]

- Add support for these options:
  `-wolfssl`, `-wolfssh`, `-mbedtls`, `-libssh`, `-psl`

  Caveats:
  - `-wolfssh` requires `-wolfssl`.
  - `-wolfssl` cannot be used with OpenSSL backends in parallel.
  - `-libssh` has build issues with BoringSSL and LibreSSL, and also
     what looks like a world-writable-config vulnerability on Windows.
     Consider it experimental.
  - `-psl` requires `-idn2` and extra libs passed via
    `LIBS=-liconv -lunistring`.

- Detect BoringSSL/wolfSSL and set ngtcp2 crypto lib accordingly.
- Generalize MultiSSL detection.
- Use else-if syntax. Requires GNU Make 3.81 (2006-04-01).
- Document more customization options.

This brings over some configuration logic from `curl-for-win`.

Closes #9680