net: usb: lan78xx: Fix error message format specifier

Display the return code as decimal integer.

Fixes: 55d7de9d ("Microchip's LAN7800 family USB 2/3 to 10/100/1000 Ethernet device driver")
Signed-off-by: Cristian Birsan <cristian.birsan@microchip.com>
Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com>

drivers/net/usb/lan78xx.c

@@ -511,7 +511,7 @@ static int lan78xx_read_stats(struct lan78xx_net *dev,
 		}
 	} else {
 		netdev_warn(dev->net,
-			    "Failed to read stat ret = 0x%x", ret);
+			    "Failed to read stat ret = %d", ret);
 	}
 
 	kfree(stats);