[media] V4L: soc_camera_platform: do not leave dangling invalid pointers

The life-time of soc-camera device objects can be longer, than the
time, it is attached to a client driver, therefore all references to
the driver own data have to be cleared, when the driver is detached.

Signed-off-by: Guennadi Liakhovetski <g.liakhovetski@gmx.de>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>

drivers/media/video/soc_camera_platform.c

@@ -173,7 +173,9 @@ evdrs:
 static int soc_camera_platform_remove(struct platform_device *pdev)
 {
 	struct soc_camera_platform_priv *priv = get_priv(pdev);
+	struct soc_camera_platform_info *p = v4l2_get_subdevdata(&priv->subdev);
 
+	p->icd->control = NULL;
 	v4l2_device_unregister_subdev(&priv->subdev);
 	platform_set_drvdata(pdev, NULL);
 	kfree(priv);