[media] cx23885: Don't use memset on vidioc_ callbacks

vidioc_g_tuner should not do any memset for the parameters. Core
already does that. In particular, V4L2 core now does some handling
for the tuner type, and the tuner-core module relies on that.

So, doing any memset there is a very bad idea.
Signed-off-by: NMauro Carvalho Chehab <mchehab@redhat.com>

drivers/media/video/cx23885/cx23885-video.c

@@ -1223,7 +1223,6 @@ static int vidioc_g_tuner(struct file *file, void *priv,
 	if (0 != t->index)
 		return -EINVAL;
 
-	memset(t, 0, sizeof(*t));
 	strcpy(t->name, "Television");
 
 	return 0;