bluetooth: bfusb: Replace GFP_ATOMIC with GFP_KERNEL in bfusb_send_frame()

bfusb_send_frame() is only set to hdev->send, and hdev->send() is never
called in atomic context.

bfusb_send_frame() calls bt_skb_alloc() with GFP_ATOMIC, which is not
necessary. GFP_ATOMIC can be replaced with GFP_KERNEL.

This is found by a static analysis tool named DCNS written by myself.
I also manually check the kernel code before reporting it.
Signed-off-by: Jia-Ju Bai <baijiaju1990@gmail.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>

drivers/bluetooth/bfusb.c

@@ -490,7 +490,7 @@ static int bfusb_send_frame(struct hci_dev *hdev, struct sk_buff *skb)
 	count = skb->len;
 
 	/* Max HCI frame size seems to be 1511 + 1 */
-	nskb = bt_skb_alloc(count + 32, GFP_ATOMIC);
+	nskb = bt_skb_alloc(count + 32, GFP_KERNEL);
 	if (!nskb) {
 		BT_ERR("Can't allocate memory for new packet");
 		return -ENOMEM;