can: gs_usb: gs_usb_receive_bulk_callback(): make use of netdev

Make use the previously assigned variable netdev instead of using
dev->netdev.

Link: https://lore.kernel.org/all/20230718-gs_usb-cleanups-v1-5-c3b9154ec605@pengutronix.deSigned-off-by: Marc Kleine-Budde <mkl@pengutronix.de>

drivers/net/can/usb/gs_usb.c

@@ -565,7 +565,7 @@ static void gs_usb_receive_bulk_callback(struct urb *urb)
 
 	if (hf->echo_id == -1) { /* normal rx */
 		if (hf->flags & GS_CAN_FLAG_FD) {
-			skb = alloc_canfd_skb(dev->netdev, &cfd);
+			skb = alloc_canfd_skb(netdev, &cfd);
 			if (!skb)
 				return;
 
@@ -578,7 +578,7 @@ static void gs_usb_receive_bulk_callback(struct urb *urb)
 
 			memcpy(cfd->data, hf->canfd->data, cfd->len);
 		} else {
-			skb = alloc_can_skb(dev->netdev, &cf);
+			skb = alloc_can_skb(netdev, &cf);
 			if (!skb)
 				return;