can: rx-offload: can_rx_offload_offload_one(): avoid double unlikely() notation when using IS_ERR()

The definition of IS_ERR() already applies the unlikely() notation when
checking the error status of the passed pointer. For this reason there is no
need to have the same notation outside of IS_ERR() itself.

Clean up code by removing redundant notation.
Signed-off-by: Antonio Quartulli <a@unstable.cc>
Link: https://lore.kernel.org/r/20201210085321.18693-1-a@unstable.ccSigned-off-by: Marc Kleine-Budde <mkl@pengutronix.de>

drivers/net/can/rx-offload.c

@@ -157,7 +157,7 @@ can_rx_offload_offload_one(struct can_rx_offload *offload, unsigned int n)
 	/* There was a problem reading the mailbox, propagate
 	 * error value.
 	 */
-	if (unlikely(IS_ERR(skb))) {
+	if (IS_ERR(skb)) {
 		offload->dev->stats.rx_dropped++;
 		offload->dev->stats.rx_fifo_errors++;