Don't look for images if we already found one

Oops. :)

Author: aheckler

functions.opengraph.php

@@ -155,7 +155,7 @@ function jetpack_og_get_image( $width = 200, $height = 200, $max_images = 4 ) {
 		}
 
 		// Attempt to find something good for this post using our generalized PostImages code
-		if ( class_exists( 'Jetpack_PostImages' ) ) {
+		if ( !$image && class_exists( 'Jetpack_PostImages' ) ) {
 			$post_images = Jetpack_PostImages::get_images( $post->ID, array( 'width' => $width, 'height' => $height ) );
 			if ( $post_images && !is_wp_error( $post_images ) ) {
 				$image = array();