Add size limit to X509_NAME structure.
Add size limit to X509_NAME structure.

This adds an explicit limit to the size of an X509_NAME structure. Some
part of OpenSSL (e.g. TLS) already effectively limit the size due to
restrictions on certificate size.

Reviewed-by: Matt Caswell <1fa2ef4755a9226cb9a0a4840bd89b158ac71391@openssl.org>

openssl/openssl,openssl/openssl,openssl/openssl,openssl/openssl,openssl/openssl,openssl/openssl