[php-src] PR #23534: ext/hash: report argument #2 ($filename) for null bytes in hash_file()

Pull Request: https://github.com/php/php-src/pull/23534 Author: lacatoire php_hash_do_hash() hardcodes argument index 1 in its isfilename branch, so hash_file() blames $algo for a null byte that was carried by $filename. hash_file() is the only caller passing isfilename = 1, and its filename is argument #2. Before: ``` ValueError: hash_file(): Argument #1 ($algo) must not contain any null bytes ``` After: ``` ValueError: hash_file(): Argument #2 ($filename) must not contain any null bytes ``` php_hash_do_hash_hmac() already reports 2 for the same check, so hash_hmac_file() was right and hash_file() was the odd one out. Only the error message changes; a test case is added.