Fix a variable typo in `get_post_gallery_images()`.

props rodrigosprimo. Fixes #24202 for trunk.

git-svn-id: http://core.svn.wordpress.org/trunk@24837 1a063a9b-81f0-0310-95a4-ce76da25c4cd

wp-includes/media.php

@@ -2017,6 +2017,6 @@ function get_post_galleries_images( $post = 0 ) {
  * @return array A list of a gallery's image srcs in order
  */
 function get_post_gallery_images( $post = 0 ) {
-	$galleries = get_post_gallery( $post, false );
+	$gallery = get_post_gallery( $post, false );
 	return empty( $gallery['src'] ) ? array() : $gallery['src'];
 }