crypto: DSA parameter validation in FIPS mode

FIPS 180-4 requires specific (L,N) values. OpenSSL will crash if an
invalid combination is used, so we must check the input sanity first.

PR-URL: https://github.com/nodejs/node/pull/3756


Reviewed-By: Fedor Indutny <fedor.indutny@gmail.com>
Reviewed-By: Shigeki Ohtsu <ohtsu@iij.ad.jp>
Reviewed-By: James M Snell <jasnell@gmail.com>