can: raw: raw_sendmsg(): remove not needed setting of skb->sk

can: raw: raw_sendmsg(): remove not needed setting of skb->sk

The skb in raw_sendmsg() is allocated with sock_alloc_send_skb(),
which subsequently calls sock_alloc_send_pskb() -> skb_set_owner_w(),
which assigns "skb->sk = sk".

This patch removes the not needed setting of skb->sk.

Link: https://lore.kernel.org/all/20220502091946.1916211-2-mkl@pengutronix.de
Acked-by: Oliver Hartkopp <socketcan@hartkopp.net>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>