wifi: libertas: cmdresp: don't call kfree_skb() under spin_lock_irqsave()

wifi: libertas: cmdresp: don't call kfree_skb() under spin_lock_irqsave()

It is not allowed to call kfree_skb() from hardware interrupt
context or with interrupts being disabled. So replace kfree_skb()
with dev_kfree_skb_irq() under spin_lock_irqsave(). Compile
tested only.

Fixes: f52b041aed77 ("libertas: Add spinlock to avoid race condition")
Signed-off-by: Yang Yingliang <yangyingliang@huawei.com>
Signed-off-by: Kalle Valo <kvalo@kernel.org>
Link: https://lore.kernel.org/r/20221207150008.111743-5-yangyingliang@huawei.com