build: add node_use_openssl check to install.py

When configuring --without-ssl and then running make install
openssl headers will be copied from deps/openssl to the target
installation directory.

This commit adds a check for is node_use_openssl is set in which
case the headers are not copied.

PR-URL: https://github.com/nodejs/node/pull/11766


Reviewed-By: Colin Ihrig <cjihrig@gmail.com>
Reviewed-By: Ben Noordhuis <info@bnoordhuis.nl>
Reviewed-By: Brian White <mscdex@mscdex.net>