can: grcan: fix spelling mistake "buss" -> "bus"

There is a spelling mistake in a netdev_err error message. Fix it.
Signed-off-by: Colin Ian King <colin.king@canonical.com>
Link: https://lore.kernel.org/r/20200806105616.46790-1-colin.king@canonical.comSigned-off-by: Marc Kleine-Budde <mkl@pengutronix.de>

drivers/net/can/grcan.c

@@ -726,7 +726,7 @@ static void grcan_err(struct net_device *dev, u32 sources, u32 status)
 			txrx = "on rx ";
 			stats->rx_errors++;
 		}
-		netdev_err(dev, "Fatal AHB buss error %s- halting device\n",
+		netdev_err(dev, "Fatal AHB bus error %s- halting device\n",
 			   txrx);
 
 		spin_lock_irqsave(&priv->lock, flags);