[openssl/openssl] fce1cb: Set RC4 defines on libcrypto/liblegacy

[Tomáš Mráz]

  Branch: refs/heads/openssl-3.0
  Home:   https://github.com/openssl/openssl
  Commit: fce1cb15d8d3bddbd68d23eb206ef95f902778d9
      https://github.com/openssl/openssl/commit/fce1cb15d8d3bddbd68d23eb206ef95f902778d9
  Author: Tomas Mraz <tomas at openssl.org>
  Date:   2023-06-10 (Sat, 10 Jun 2023)

  Changed paths:
    M crypto/rc4/build.info
    M providers/implementations/ciphers/cipher_rc4_hmac_md5.h

  Log Message:
  -----------
  Set RC4 defines on libcrypto/liblegacy

Also add missing prototype for rc4_md5_enc.

Fixes #21150

Reviewed-by: Matt Caswell <matt at openssl.org>
Reviewed-by: Paul Dale <pauli at openssl.org>
(Merged from https://github.com/openssl/openssl/pull/21153)

(cherry picked from commit 58e8af4cecd23dbea2e6b061ab68190b38d64145)