Add Post Type Templates (WordPress 4.7) To ACF Add Field Group

acf.php

<?php 

add_filter('acf/location/rule_values/page_template', function($val) {
	$post_types = get_post_types(array('public' => true), 'objects');
	$new_values = array();
	foreach($post_types as $post_type) {
		$values = array();
		$items = get_page_templates( null, $post_type->name );
		foreach($items as $name => $item) {
			$values[$item] = $name;
		}
		$new_values[$post_type->label] = $values;
	}
	return $new_values;
});