Only display Jetpack Ads on posts

jetpack-ads-posts-only.php

<?php // Remove this line if copy/pasting to an existing file.
/*
Plugin Name: Only Display Jetpack Ads on Posts
Plugin URI: https://kraft.blog
Description: Only output Jetpack Ads on posts and no other post type.
Author: Kraft
Author URI: https://kraft.im/
Version: 2016.06.15
License: GPL
*/

add_action( 'wp', 'bk_limit_jetpack_ads_posts' );

function bk_limit_jetpack_ads_posts(){
  if ( get_post_type() != 'post' ){
    add_filter( 'wordads_inpost_disable', '__return_true' );
  }
}