[media] exynos4-is: Add missing v4l2_device_unregister() call in fimc_md_remove()

Signed-off-by: NSylwester Nawrocki <s.nawrocki@samsung.com>
Signed-off-by: NKyungmin Park <kyungmin.park@samsung.com>
Signed-off-by: NMauro Carvalho Chehab <m.chehab@samsung.com>

drivers/media/platform/exynos4-is/media-dev.c

@@ -1544,6 +1544,8 @@ static int fimc_md_remove(struct platform_device *pdev)
 
 	if (!fmd)
 		return 0;
+
+	v4l2_device_unregister(&fmd->v4l2_dev);
 	device_remove_file(&pdev->dev, &dev_attr_subdev_conf_mode);
 	fimc_md_unregister_entities(fmd);
 	fimc_md_pipelines_free(fmd);