typings: define types for os binding

PR-URL: https://github.com/nodejs/node/pull/40222


Reviewed-By: Tobias Nießen <tniessen@tnie.de>
Reviewed-By: Evan Lucas <evanlucas@me.com>
Reviewed-By: Zijian Liu <lxxyxzj@gmail.com>
Reviewed-By: James M Snell <jasnell@gmail.com>
Reviewed-By: Michael Dawson <midawson@redhat.com>