XML-RPC: Remove unused wpdb global in `wp_xmlrpc_server::mw_newMedi…

…aObject()`.

Follow-up to [2676], [4961], [5008], [24716], [34578].

Props upadalavipul.
See #59185.

git-svn-id: https://develop.svn.wordpress.org/trunk@56480 602fd350-edb4-49c9-b593-d223f7449a82

src/wp-includes/class-wp-xmlrpc-server.php

@@ -6370,8 +6370,6 @@ public function mw_getCategories( $args ) {
 	 *
 	 * @since 1.5.0
 	 *
-	 * @global wpdb $wpdb WordPress database abstraction object.
-	 *
 	 * @param array $args {
 	 *     Method arguments. Note: arguments must be ordered as documented.
 	 *
@@ -6383,8 +6381,6 @@ public function mw_getCategories( $args ) {
 	 * @return array|IXR_Error
 	 */
 	public function mw_newMediaObject( $args ) {
-		global $wpdb;
-
 		$username = $this->escape( $args[1] );
 		$password = $this->escape( $args[2] );
 		$data     = $args[3];