lan78xx: Fix memory leaks

In lan78xx_probe(), a new urb is allocated through usb_alloc_urb() and
saved to 'dev->urb_intr'. However, in the following execution, if an error
occurs, 'dev->urb_intr' is not deallocated, leading to memory leaks. To fix
this issue, invoke usb_free_urb() to free the allocated urb before
returning from the function.
Signed-off-by: NWenwen Wang <wenwen@cs.uga.edu>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

drivers/net/usb/lan78xx.c

@@ -3792,7 +3792,7 @@ static int lan78xx_probe(struct usb_interface *intf,
 	ret = register_netdev(netdev);
 	if (ret != 0) {
 		netif_err(dev, probe, netdev, "couldn't register the device\n");
-		goto out3;
+		goto out4;
 	}
 
 	usb_set_intfdata(intf, dev);
@@ -3807,12 +3807,14 @@ static int lan78xx_probe(struct usb_interface *intf,
 
 	ret = lan78xx_phy_init(dev);
 	if (ret < 0)
-		goto out4;
+		goto out5;
 
 	return 0;
 
-out4:
+out5:
 	unregister_netdev(netdev);
+out4:
+	usb_free_urb(dev->urb_intr);
 out3:
 	lan78xx_unbind(dev, intf);
 out2: