crypto: don't build hardware engines

Compile out hardware engines.

`ENGINE_load_builtin_engines()` is not called in v0.10 so this does
not represent a known security vulnerability.

Backport of
https://github.com/nodejs/node-private/pull/58

PR-URL: https://github.com/nodejs/node-private/pull/68


Reviewed-By: Fedor Indutny <fedor.indutny@gmail.com>
Reviewed-By: Ben Noordhuis <info@bnoordhuis.nl>