Bluetooth: hci_bcsp: 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().

Fixes: 1da177e4 ("Linux-2.6.12-rc2")
Signed-off-by: Yang Yingliang <yangyingliang@huawei.com>
Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com>

drivers/bluetooth/hci_bcsp.c

@@ -378,7 +378,7 @@ static void bcsp_pkt_cull(struct bcsp_struct *bcsp)
 		i++;
 
 		__skb_unlink(skb, &bcsp->unack);
-		kfree_skb(skb);
+		dev_kfree_skb_irq(skb);
 	}
 
 	if (skb_queue_empty(&bcsp->unack))