[openssl/openssl] b207e0: doc: note that out ChaCha20 isn't standard compliant.

[Pauli]

  Branch: refs/heads/openssl-3.1
  Home:   https://github.com/openssl/openssl
  Commit: b207e0e4f994a003faefaba5c798e3060ef2eafa
      https://github.com/openssl/openssl/commit/b207e0e4f994a003faefaba5c798e3060ef2eafa
  Author: Pauli <pauli at openssl.org>
  Date:   2023-06-06 (Tue, 06 Jun 2023)

  Changed paths:
    M doc/man3/EVP_chacha20.pod

  Log Message:
  -----------
  doc: note that out ChaCha20 isn't standard compliant.

Fixes #21095

Reviewed-by: Tomas Mraz <tomas at openssl.org>
Reviewed-by: Shane Lontis <shane.lontis at oracle.com>
(Merged from https://github.com/openssl/openssl/pull/21098)

(cherry picked from commit c69756e7a0133b67df50525e89206c9cc4a7d2b8)