usb: gadget: configs: plug memory leak

When binding a gadget to a device, "name" is stored in gi->udc_name, but
this does not happen when unregistering and the string is leaked.
Signed-off-by: NJohn Keeping <john@metanate.com>
Signed-off-by: NFelipe Balbi <felipe.balbi@linux.intel.com>

drivers/usb/gadget/configfs.c

@@ -269,6 +269,7 @@ static ssize_t gadget_dev_desc_UDC_store(struct config_item *item,
 		ret = unregister_gadget(gi);
 		if (ret)
 			goto err;
+		kfree(name);
 	} else {
 		if (gi->composite.gadget_driver.udc_name) {
 			ret = -EBUSY;