V4L/DVB (9667): Fixed typo in sizeof() causing NULL pointer OOPS

Signed-off-by: Oldřich Jedlička <oldium.pro@seznam.cz>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
diff --git a/drivers/media/video/saa7134/saa7134-cards.c b/drivers/media/video/saa7134/saa7134-cards.c
index ddc5402..8635228 100644
--- a/drivers/media/video/saa7134/saa7134-cards.c
+++ b/drivers/media/video/saa7134/saa7134-cards.c
@@ -6048,7 +6048,7 @@
 		struct v4l2_priv_tun_config  xc2028_cfg;
 		struct xc2028_ctrl           ctl;
 
-		memset(&xc2028_cfg, 0, sizeof(ctl));
+		memset(&xc2028_cfg, 0, sizeof(xc2028_cfg));
 		memset(&ctl, 0, sizeof(ctl));
 
 		ctl.fname   = XC2028_DEFAULT_FIRMWARE;