Ensure OSSL_PARAM_BLD_free() can accept a NULL
Ensure OSSL_PARAM_BLD_free() can accept a NULL

All OpenSSL free functions should accept NULL.

Reviewed-by: Shane Lontis <452ce16516ceed26291fe7de3f8b53540d83864e@oracle.com>
(Merged from https://github.com/openssl/openssl/pull/11635)

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