USB: misc: trancevibrator: fix up a sysfs attribute permission

It should not be writable by any user.
Reported-by: NLinus Torvalds <torvalds@linux-foundation.org>
Cc: Sam Hocevar <sam@zoy.org>
Cc: stable <stable@kernel.org>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

drivers/usb/misc/trancevibrator.c

@@ -86,7 +86,7 @@ static ssize_t set_speed(struct device *dev, struct device_attribute *attr,
 	return count;
 }
 
-static DEVICE_ATTR(speed, S_IWUGO | S_IRUGO, show_speed, set_speed);
+static DEVICE_ATTR(speed, S_IRUGO | S_IWUSR, show_speed, set_speed);
 
 static int tv_probe(struct usb_interface *interface,
 		    const struct usb_device_id *id)