NULL-check for cipher is redundant, instead check if cipher->name is NULL
While here fix formatting of BIO_printf calls as suggested by Andy Polyakov.
CLA: trivial
Reviewed-by: Andy Polyakov <appro@openssl.org>
Reviewed-by: Rich Salz <rsalz@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/6282)