warnings cleanup on archived/suspended sites, fixes #12396

git-svn-id: http://svn.automattic.com/wordpress/trunk@13461 1a063a9b-81f0-0310-95a4-ce76da25c4cd

wp-admin/includes/ms.php

@@ -48,6 +48,7 @@ add_filter( 'wp_handle_upload_prefilter', 'check_upload_size' );
 function wpmu_delete_blog($blog_id, $drop = false) {
 	global $wpdb;
 
+	$switched = false;
 	if ( $blog_id != $wpdb->blogid ) {
 		$switch = true;
 		switch_to_blog($blog_id);