src: drop CNNIC+StartCom certificate whitelisting

Remove the CNNIC certificates again and remove the whitelist from commit
3beb8807 ("crypto: add cert check to CNNIC Whitelist") from June 2015.

PR-URL: https://github.com/nodejs/node/pull/19322


Reviewed-By: Fedor Indutny <fedor.indutny@gmail.com>
Reviewed-By: Colin Ihrig <cjihrig@gmail.com>
Reviewed-By: Daniel Bevenius <daniel.bevenius@gmail.com>
Reviewed-By: James M Snell <jasnell@gmail.com>