Fix EVP_PKEY_CTX_ctrl() documentation

Remove references to 'macro' from EVP_PKEY_CTX_ctrl() as they are all
functions now, and update the HISTORY section.
Reviewed-by: NNicola Tuveri <nic.tuv@gmail.com>
Reviewed-by: NRichard Levitte <levitte@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/12853)