can: kvaser_usb_hydra: do not report txerr and rxerr during bus-off

During bus off, the error count is greater than 255 and can not fit in
a u8.

Fixes: aec5fb22 ("can: kvaser_usb: Add support for Kvaser USB hydra family")
Link: https://lore.kernel.org/all/20220719143550.3681-8-mailhol.vincent@wanadoo.fr
CC: Jimmy Assarsson <extja@kvaser.com>
Signed-off-by: Vincent Mailhol <mailhol.vincent@wanadoo.fr>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>

drivers/net/can/usb/kvaser_usb/kvaser_usb_hydra.c

@@ -917,8 +917,10 @@ static void kvaser_usb_hydra_update_state(struct kvaser_usb_net_priv *priv,
 	    new_state < CAN_STATE_BUS_OFF)
 		priv->can.can_stats.restarts++;
 
-	cf->data[6] = bec->txerr;
-	cf->data[7] = bec->rxerr;
+	if (new_state != CAN_STATE_BUS_OFF) {
+		cf->data[6] = bec->txerr;
+		cf->data[7] = bec->rxerr;
+	}
 
 	netif_rx(skb);
 }
@@ -1069,8 +1071,10 @@ kvaser_usb_hydra_error_frame(struct kvaser_usb_net_priv *priv,
 	shhwtstamps->hwtstamp = hwtstamp;
 
 	cf->can_id |= CAN_ERR_BUSERROR;
-	cf->data[6] = bec.txerr;
-	cf->data[7] = bec.rxerr;
+	if (new_state != CAN_STATE_BUS_OFF) {
+		cf->data[6] = bec.txerr;
+		cf->data[7] = bec.rxerr;
+	}
 
 	netif_rx(skb);