USB: usbtmc: remove unnecessary memory allocation

Inside usbtmc_ioctl_clear_out_halt()/usbtmc_ioctl_clear_in_halt(),
usb_clear_halt() needn't any buffer to pass in, so remove the
unnecessary memory allocation.
Signed-off-by: Ming Lei <ming.lei@canonical.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/usb/class/usbtmc.c

@@ -718,50 +718,32 @@ static int usbtmc_ioctl_clear(struct usbtmc_device_data *data)
 
 static int usbtmc_ioctl_clear_out_halt(struct usbtmc_device_data *data)
 {
-	u8 *buffer;
 	int rv;
 
-	buffer = kmalloc(2, GFP_KERNEL);
-	if (!buffer)
-		return -ENOMEM;
-
 	rv = usb_clear_halt(data->usb_dev,
 			    usb_sndbulkpipe(data->usb_dev, data->bulk_out));
 
 	if (rv < 0) {
 		dev_err(&data->usb_dev->dev, "usb_control_msg returned %d\n",
 			rv);
-		goto exit;
-	}
-	rv = 0;
-
-exit:
-	kfree(buffer);
 		return rv;
+	}
+	return 0;
 }
 
 static int usbtmc_ioctl_clear_in_halt(struct usbtmc_device_data *data)
 {
-	u8 *buffer;
 	int rv;
 
-	buffer = kmalloc(2, GFP_KERNEL);
-	if (!buffer)
-		return -ENOMEM;
-
 	rv = usb_clear_halt(data->usb_dev,
 			    usb_rcvbulkpipe(data->usb_dev, data->bulk_in));
 
 	if (rv < 0) {
 		dev_err(&data->usb_dev->dev, "usb_control_msg returned %d\n",
 			rv);
-		goto exit;
-	}
-	rv = 0;
-
-exit:
-	kfree(buffer);
 		return rv;
+	}
+	return 0;
 }
 
 static int get_capabilities(struct usbtmc_device_data *data)