usb: gadget: udc: core: remove usage of list iterator past the loop body

To move the list iterator variable into the list_for_each_entry_*()
macro in the future it should be avoided to use the list iterator
variable after the loop body.

To *never* use the list iterator variable after the loop it was
concluded to use a separate iterator variable [1].

Link: https://lore.kernel.org/all/YhdfEIwI4EdtHdym@kroah.com/
Signed-off-by: Jakob Koschel <jakobkoschel@gmail.com>
Link: https://lore.kernel.org/r/20220308171818.384491-25-jakobkoschel@gmail.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/usb/gadget/udc/core.c

@@ -1528,18 +1528,20 @@ static int udc_bind_to_driver(struct usb_udc *udc, struct usb_gadget_driver *dri
 
 int usb_gadget_probe_driver(struct usb_gadget_driver *driver)
 {
-	struct usb_udc		*udc = NULL;
+	struct usb_udc		*udc = NULL, *iter;
 	int			ret = -ENODEV;
 
 	if (!driver || !driver->bind || !driver->setup)
 		return -EINVAL;
 
 	mutex_lock(&udc_lock);
 	if (driver->udc_name) {
-		list_for_each_entry(udc, &udc_list, list) {
-			ret = strcmp(driver->udc_name, dev_name(&udc->dev));
-			if (!ret)
-				break;
+		list_for_each_entry(iter, &udc_list, list) {
+			ret = strcmp(driver->udc_name, dev_name(&iter->dev));
+			if (ret)
+				continue;
+			udc = iter;
+			break;
 		}
 		if (ret)
 			ret = -ENODEV;
@@ -1548,10 +1550,12 @@ int usb_gadget_probe_driver(struct usb_gadget_driver *driver)
 		else
 			goto found;
 	} else {
-		list_for_each_entry(udc, &udc_list, list) {
+		list_for_each_entry(iter, &udc_list, list) {
 			/* For now we take the first one */
-			if (!udc->driver)
-				goto found;
+			if (iter->driver)
+				continue;
+			udc = iter;
+			goto found;
 		}
 	}