can: netlink: can_changelink(): convert from netdev_err() to NL_SET_ERR_MSG_FMT()

Since commit 51c352bd ("netlink: add support for formatted extack
messages") formatted extack messages are supported to inform the user
space or warnings/errors during netlink calls.

Replace the netdev_err() by NL_SET_ERR_MSG_FMT() to better inform the
user about the problem. While there, use %u to print unsigned values
and improve error message a bit.

Link: https://lore.kernel.org/all/20230202110854.2318594-9-mkl@pengutronix.deSigned-off-by: Marc Kleine-Budde <mkl@pengutronix.de>

drivers/net/can/dev/netlink.c

@@ -220,8 +220,9 @@ static int can_changelink(struct net_device *dev, struct nlattr *tb[],
 			return err;
 
 		if (priv->bitrate_max && bt.bitrate > priv->bitrate_max) {
-			netdev_err(dev, "arbitration bitrate surpasses transceiver capabilities of %d bps\n",
-				   priv->bitrate_max);
+			NL_SET_ERR_MSG_FMT(extack,
+					   "arbitration bitrate %u bps surpasses transceiver capabilities of %u bps",
+					   bt.bitrate, priv->bitrate_max);
 			return -EINVAL;
 		}
 
@@ -324,8 +325,9 @@ static int can_changelink(struct net_device *dev, struct nlattr *tb[],
 			return err;
 
 		if (priv->bitrate_max && dbt.bitrate > priv->bitrate_max) {
-			netdev_err(dev, "canfd data bitrate surpasses transceiver capabilities of %d bps\n",
-				   priv->bitrate_max);
+			NL_SET_ERR_MSG_FMT(extack,
+					   "CANFD data bitrate %u bps surpasses transceiver capabilities of %u bps",
+					   dbt.bitrate, priv->bitrate_max);
 			return -EINVAL;
 		}