unified them.
- return (0); -> return 0;
- return (1); -> return 1;
- return (-1); -> return -1;
Reviewed-by: NStephen Henson <steve@openssl.org>
Reviewed-by: NMatt Caswell <matt@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/4500)