Bluetooth: hci_uart: Add setup callback

Some Bluetooth controllers require initialization before being
used (vendor config, firmware download). Add possibility for a
HCI UART proto to implement this early init via the setup callback.

Signed-off-by: Loic Poulain <loic.poulain@intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
diff --git a/drivers/bluetooth/hci_uart.h b/drivers/bluetooth/hci_uart.h
index 247488e..074ed29 100644
--- a/drivers/bluetooth/hci_uart.h
+++ b/drivers/bluetooth/hci_uart.h
@@ -59,6 +59,7 @@
 	int (*flush)(struct hci_uart *hu);
 	int (*recv)(struct hci_uart *hu, void *data, int len);
 	int (*enqueue)(struct hci_uart *hu, struct sk_buff *skb);
+	int (*setup)(struct hci_uart *hu);
 	struct sk_buff *(*dequeue)(struct hci_uart *hu);
 };