Staging: comedi: unlock on error in usbduxsigma_attach()

We should release the udev->sem lock before returning.
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

drivers/staging/comedi/drivers/usbduxsigma.c

@@ -2691,6 +2691,7 @@ static int usbduxsigma_attach(struct comedi_device *dev,
 	if (ret < 0) {
 		dev_err(&udev->interface->dev,
 			"comedi%d: no space for subdev\n", dev->minor);
+		up(&udev->sem);
 		up(&start_stop_sem);
 		return ret;
 	}