This post tells how to create php.ini symbolic links in all your domain folders and subfolders. But what if you want to get rid of them? I edited the script to delete them in case you dont want it anymore.

<?php

// File and path names for your host and website.
$host_php_ini  = "/usr/local/lib/php.ini";     // your host's php.ini file (see phpinfo())
$local_php_ini = "/home/**your username**/local_php.ini";  // your modified php.ini will go here
$website_root  = "/home/**your username**/public_html";    // your website's root

// Walk website directory tree, inserting symbolic links to modified php.ini file.
$nodes = new RecursiveIteratorIterator(new RecursiveDirectoryIterator($website_root),
                                       RecursiveIteratorIterator::SELF_FIRST);
foreach ($nodes as $node) {
    if ($node->isDir()) {
        $linkpath = $node->getPathname() . "/php.ini";
        if(is_link($linkpath)) {
        unlink($linkpath);
        },
    }
}

?>