Bluetooth: btintel: Add support for enabling tracing functionality

For Intel controllers with firmware that allows tracing of baseband
functionality this allows enabling it via set_diag driver callback.

Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
diff --git a/drivers/bluetooth/btusb.c b/drivers/bluetooth/btusb.c
index cd5e6ff..e9142a4 100644
--- a/drivers/bluetooth/btusb.c
+++ b/drivers/bluetooth/btusb.c
@@ -2882,6 +2882,7 @@
 		hdev->send = btusb_send_frame_intel;
 		hdev->setup = btusb_setup_intel_new;
 		hdev->hw_error = btintel_hw_error;
+		hdev->set_diag = btintel_set_diag;
 		hdev->set_bdaddr = btintel_set_bdaddr;
 		set_bit(HCI_QUIRK_STRICT_DUPLICATE_FILTER, &hdev->quirks);
 	}