fix(macOS): SEGV proc_open on macOS 15

[zeriyoshi]

Building master on macOS 15 causes a segfault in proc_open and crashes the process.

As a workaround, use the _np variant on older macOS and suppress the deprecation warnings.

$ PATH="/opt/homebrew/opt/bison/bin:/opt/homebrew/opt/re2c/bin:$PATH" ./buildconf --force
$ PATH="/opt/homebrew/opt/bison/bin:/opt/homebrew/opt/re2c/bin:$PATH" ./configure --disable-all --disable-phpdbg --disable-cgi --disable-fpm --enable-cli
$ PATH="/opt/homebrew/opt/bison/bin:/opt/homebrew/opt/re2c/bin:$PATH" make -j10
$ ./sapi/cli/php run-tests.php ext/standard/tests/general_functions/proc_open_cwd_basic.phpt

=====================================================================
PHP         : /Users/g-kudo/Developments/zeriyoshi-php-src/sapi/cli/php 
PHP_SAPI    : cli
PHP_VERSION : 8.6.0-dev
ZEND_VERSION: 4.6.0-dev
PHP_OS      : Darwin - Darwin MA-391.local 24.6.0 Darwin Kernel Version 24.6.0: Mon Jan 19 22:01:41 PST 2026; root:xnu-11417.140.69.708.3~1/RELEASE_ARM64_T8132 arm64
INI actual  : /Users/g-kudo/Developments/zeriyoshi-php-src
More .INIs  :   
CWD         : /Users/g-kudo/Developments/zeriyoshi-php-src
Extra dirs  : 
VALGRIND    : Not used
=====================================================================
Running selected tests.
Segmentation fault: 11     ./sapi/cli/php run-tests.php ext/standard/tests/general_functions/proc_open_cwd_basic.phpt