The following new functions all do the same thing; they traverse
the set of names assigned to implementations of each algorithm type:

EVP_MD_names_do_all(), EVP_CIPHER_names_do_all(),
EVP_MAC_names_do_all(), EVP_KEYMGMT_names_do_all(),
EVP_KEYEXCH_names_do_all(), EVP_KDF_names_do_all(),
EVP_SIGNATURE_names_do_all()

We add a warning to the documentation of EVP_CIPHER_name() and
EVP_MD_name(), as they aren't suitable to use with multiple-name
implementation.

We also remove EVP_MAC_name() and evp_KDF_name(), as they serve no
useful purpose.
Reviewed-by: NTomas Mraz <tmraz@fedoraproject.org>
(Merged from https://github.com/openssl/openssl/pull/9979)