vfio-mdev: remove some dead code

We set info.count to 1 in mtty_get_irq_info() so static checkers
complain that, "Why do we have impossible conditions?"  The answer is
that it seems to be left over dead code that can be safely removed.
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Reviewed-by: Kirti Wankhede <kwankhede@nvidia.com>
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>

samples/vfio-mdev/mtty.c

@@ -1230,9 +1230,6 @@ static long mtty_ioctl(struct mdev_device *mdev, unsigned int cmd,
 		if (ret)
 			return ret;
 
-		if (info.count == -1)
-			return -EINVAL;
-
 		if (copy_to_user((void __user *)arg, &info, minsz))
 			return -EFAULT;