Bluetooth: btusb: Comment on unbalanced pm reference

Add a comment clarifying that a PM reference in btusb_qca_cmd_timeout is
not unbalanced because it results in a device reset.
Signed-off-by: Abhishek Pandit-Subedi <abhishekpandit@chromium.org>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>

drivers/bluetooth/btusb.c

@@ -581,6 +581,7 @@ static void btusb_qca_cmd_timeout(struct hci_dev *hdev)
 		return;
 
 	bt_dev_err(hdev, "Multiple cmd timeouts seen. Resetting usb device.");
+	/* This is not an unbalanced PM reference since the device will reset */
 	err = usb_autopm_get_interface(data->intf);
 	if (!err)
 		usb_queue_reset_device(data->intf);