[php-src] Issue #8401: is_callable($deprecated_callable), etc., should throw a deprecation notice

Issue: https://github.com/php/php-src/issues/8401 Comment Author: claudepache With the proposed change, we lose the possibility to feed is_callable() with arbitrary input without triggering a deprecation warning in PHP 8.x (x ≥ 3), save resorting to @. However, in real world, is_callable() is almost never given _totally_ arbitrary stuff (e.g., when the stuff includes the string "static", that string is usually hard-coded somewhere); so that it is not an issue in practice.