src,lib: remove dead `process.binding()` code

There are no non-internal builtin modules left, so this
should be safe to remove to a large degree.

PR-URL: https://github.com/nodejs/node/pull/25829


Reviewed-By: Joyee Cheung <joyeec9h3@gmail.com>
Reviewed-By: Colin Ihrig <cjihrig@gmail.com>
Reviewed-By: Anto Aravinth <anto.aravinth.cse@gmail.com>
Reviewed-By: Gus Caplan <me@gus.host>
Reviewed-By: Ben Noordhuis <info@bnoordhuis.nl>