staging: comedi: remove memset() call from comedi_device_init()

`comedi_device_init()` is only called from one place
(`comedi_alloc_board_minor()`) and the `struct comedi_device` has
already been zeroed out by `kzalloc()`.  Don't bother zeroing it out
again with `memset()`.

Signed-off-by: Ian Abbott <abbotti@mev.co.uk>
Reviewed-by: H Hartley Sweeten <hsweeten@visionengravers.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/staging/comedi/comedi_fops.c

@@ -2249,7 +2249,6 @@ EXPORT_SYMBOL(comedi_event);
 
 static void comedi_device_init(struct comedi_device *dev)
 {
-	memset(dev, 0, sizeof(*dev));
 	spin_lock_init(&dev->spinlock);
 	mutex_init(&dev->mutex);
 	dev->minor = -1;