can: peak_usb: pcan_usb_fd_decode_status(): remove unnecessary test on the nullity of a pointer

Since alloc_can_err_skb() puts NULL in cf in the case when skb cannot
be allocated and can_change_state() handles the case when cf is NULL,
the test on the nullity of skb is now unnecessary.

Link: https://lore.kernel.org/all/20210929142111.55757-2-s.grosjean@peak-system.comSigned-off-by: NStephane Grosjean <s.grosjean@peak-system.com>
Signed-off-by: NMarc Kleine-Budde <mkl@pengutronix.de>

drivers/net/can/usb/peak_usb/pcan_usb_fd.c

@@ -567,8 +567,7 @@ static int pcan_usb_fd_decode_status(struct pcan_usb_fd_if *usb_if,
 
 	/* allocate an skb to store the error frame */
 	skb = alloc_can_err_skb(netdev, &cf);
-	if (skb)
-		can_change_state(netdev, cf, tx_state, rx_state);
+	can_change_state(netdev, cf, tx_state, rx_state);
 
 	/* things must be done even in case of OOM */
 	if (new_state == CAN_STATE_BUS_OFF)