wcn36xx: initialize skb_lock

ctl->skb_lock is never initialized, a fact caught by lockdep.
Signed-off-by: Bob Copeland <me@bobcopeland.com>
Signed-off-by: Kalle Valo <kvalo@codeaurora.org>

drivers/net/wireless/ath/wcn36xx/dxe.c

@@ -84,6 +84,7 @@ static int wcn36xx_dxe_allocate_ctl_block(struct wcn36xx_dxe_ch *ch)
 		if (!cur_ctl)
 			goto out_fail;
 
+		spin_lock_init(&cur_ctl->skb_lock);
 		cur_ctl->ctl_blk_order = i;
 		if (i == 0) {
 			ch->head_blk_ctl = cur_ctl;