This code started off as a copy of ssl3_write_bytes(), and the comment
was not updated with the implementation.

Reported by yangyangtiantianlonglong in #13518
Reviewed-by: NShane Lontis <shane.lontis@oracle.com>
Reviewed-by: NMatt Caswell <matt@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/13566)