display the plugin in selected posttypes

There is a filter for this purpose : page-links-to-post-types

In your functions.php, you can add this code :

add_filter('page-links-to-post-types', array('remove_plt_whatever'), 10, 1);

function remove_plt_whatever($post_types) {
    $unwanted_type_name = 'whatever';
    $key = array_search($unwanted_type_name, $post_types);
    if($key) {
        unset($post_types[$key]);
    }
    return $post_types;
}