crypto: use CHECK_NE instead of ABORT or abort

Use of abort() was added in 34febfbf4, and changed to ABORT()
in 21826ef21a, but conditional+ABORT() is better expressesed
using a CHECK_xxx() macro.

See: https://github.com/nodejs/node/pull/9409#discussion_r93575328

PR-URL: https://github.com/nodejs/node/pull/10413
Reviewed-By: Colin Ihrig <cjihrig@gmail.com>
Reviewed-By: Gibson Fahnestock <gibfahn@gmail.com>
Reviewed-By: Ben Noordhuis <info@bnoordhuis.nl>
Reviewed-By: Anna Henningsen <anna@addaleax.net>
Reviewed-By: James M Snell <jasnell@gmail.com>

src/node_crypto.cc

@@ -701,11 +701,8 @@ static X509_STORE* NewRootCertStore() {
       X509 *x509 = PEM_read_bio_X509(bp, nullptr, CryptoPemCallback, nullptr);
       BIO_free(bp);
 
-      if (x509 == nullptr) {
       // Parse errors from the built-in roots are fatal.
-        ABORT();
+      CHECK_NE(x509, nullptr);
-        return nullptr;
-      }
 
       root_certs_vector->push_back(x509);
     }