Deprecate the low level Whirlpool functions.

Deprecate the low level Whirlpool functions.

Use of the low level Whirlpool functions has been informally discouraged for a
long time.  We now formally deprecate them.

Applications should instead use the EVP APIs, e.g. EVP_Digest,
EVP_DigestInit_ex, EVP_DigestUpdate and EVP_DigestFinal_ex.

Reviewed-by: Matt Caswell <matt@openssl.org>
Reviewed-by: Tomas Mraz <tmraz@fedoraproject.org>
(Merged from https://github.com/openssl/openssl/pull/10779)