Bluetooth: Remove unused hci-destruct cb

The hci-destruct callback is not used by any driver so we can remove it.
There is no reason to keep it alive, anymore. Drivers can free their
internal data on driver-release and we do not need to provide a public
destruct callback.

Internally, we still use a destruct callback inside of hci_sysfs.c. This
one is used to correctly free our hci_dev data structure if no more
users have a reference to it.
Signed-off-by: David Herrmann <dh.herrmann@googlemail.com>
Acked-by: Marcel Holtmann <marcel@holtmann.org>
Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>

include/net/bluetooth/hci_core.h

@@ -270,7 +270,6 @@ struct hci_dev {
 	int (*close)(struct hci_dev *hdev);
 	int (*flush)(struct hci_dev *hdev);
 	int (*send)(struct sk_buff *skb);
-	void (*destruct)(struct hci_dev *hdev);
 	void (*notify)(struct hci_dev *hdev, unsigned int evt);
 	int (*ioctl)(struct hci_dev *hdev, unsigned int cmd, unsigned long arg);
 };
@@ -595,10 +594,7 @@ static inline void hci_conn_put(struct hci_conn *conn)
 /* ----- HCI Devices ----- */
 static inline void __hci_dev_put(struct hci_dev *d)
 {
-	if (atomic_dec_and_test(&d->refcnt)) {
-		if (d->destruct)
-			d->destruct(d);
-	}
+	atomic_dec(&d->refcnt);
 }
 
 /*