add_action( 'gform_delete_entry', 'delete_entry_post_id' );
function delete_entry_post_id ( $entry_id ) {
	
	$posts = get_posts(array(
		'numberposts'   => -1,
		'post_type'     => 'any',
		'meta_query'    => array(
			array(
				'key'       => 'entry_id',
				'value'     => $entry_id,
				'compare'   => '=',
			)
		),
	));



if( $posts ): 
    foreach( $posts as $post ):    
        setup_postdata( $post );
	    wp_delete_post($post->ID);
	endforeach;    
    wp_reset_postdata();
endif;	

}