[php-src] PR #24310: Fix GH-24308: Request shutdown closes a syslog handle PHP did not open

Pull Request: https://github.com/php/php-src/pull/24310 Author: lazerg The syslog RSHUTDOWN handler called php_closelog() after every request, even when nothing in the request had opened syslog. In an embedded SAPI, a host that called openlog() before running PHP lost its connection when each request ended. PHP already tracks this in PG(have_called_openlog), so the handler now checks it first. Requests that open syslog through openlog() or error_log = syslog still close it at the end. I checked it with an embed host on Debian (glibc). The host opens syslog with LOG_NDELAY and runs three requests that do not touch syslog. Before the fix, strace shows four connects to /dev/log. After the fix, it shows one. There is no test, because run-tests has no way to drive the embed SAPI with a host-owned handle. Fixes GH-24308