EVP_DecodeUpdate() should not produce padding zeros to the decoded output (Fixes #26677)

EVP_DecodeUpdate() should not produce zeros for input padding `=` signs to avoid writing to non-allocated memory regions.

To achieve this:
- Add `eof` parameter to `evp_decodeblock_int` function in `openssl/crypto/evp`. The parameter should either contain the number of the input padding characters to ignore or `-1` if the function has to count them.
- Use precalculated `eof` in `EVP_DecodeUpdate` to fix its behaviour.
- Use `eof = -1` in `EVP_DecodeFinal` to count it in `evp_decodeblock_int`.
- Do not ignore padding in `EVP_DecodeBlock` (`eof = 0`) because it should write padding zeros according to the documentation.
- Add the HISTORY section to EVP_EncodeInit documentation to describe the fix.

Other changes:
- Update AUTHORS.md
- Update the copyright date in the documentation.

Reviewed-by: Tim Hudson <tjh@openssl.org>
Reviewed-by: Viktor Dukhovni <viktor@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/26678)

doc/man3/EVP_EncodeInit.pod

@@ -176,9 +176,15 @@ EVP_DecodeBlock() returns the length of the data decoded or -1 on error.
 
 L<evp(7)>
 
+=head1 HISTORY
+
+The EVP_DecodeUpdate() function was fixed in OpenSSL 3.5,
+so now it produces the number of bytes specified in B<outl*>
+and does not decode padding bytes (B<=>) to 6 zero bits.
+
 =head1 COPYRIGHT
 
-Copyright 2016-2024 The OpenSSL Project Authors. All Rights Reserved.
+Copyright 2016-2025 The OpenSSL Project Authors. All Rights Reserved.
 
 Licensed under the Apache License 2.0 (the "License").  You may not use
 this file except in compliance with the License.  You can obtain a copy