crypto: fix scrypt keylen validation

Fixes: https://github.com/nodejs/node/issues/38381

PR-URL: https://github.com/nodejs/node/pull/38385


Reviewed-By: Nitzan Uziely <linkgoron@gmail.com>
Reviewed-By: James M Snell <jasnell@gmail.com>
Reviewed-By: Luigi Pinca <luigipinca@gmail.com>
Reviewed-By: Juan José Arboleda <soyjuanarbol@gmail.com>
Reviewed-By: Zijian Liu <lxxyxzj@gmail.com>
Reviewed-By: Darshan Sen <raisinten@gmail.com>