V4L/DVB: ivtv: sizeof() => ARRAY_SIZE()

This fixes a smatch warning:
drivers/media/video/ivtv/ivtv-vbi.c +138 ivtv_write_vbi(43)
	error: buffer overflow 'vi->cc_payload' 256 <= 1023

Signed-off-by: Dan Carpenter <error27@gmail.com>
Reviewed-by: Andy Walls <awalls@radix.net>
Signed-off-by: Andy Walls <awalls@radix.net>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
diff --git a/drivers/media/video/ivtv/ivtv-vbi.c b/drivers/media/video/ivtv/ivtv-vbi.c
index f420d31..d73af45 100644
--- a/drivers/media/video/ivtv/ivtv-vbi.c
+++ b/drivers/media/video/ivtv/ivtv-vbi.c
@@ -134,7 +134,7 @@
 			}
 		}
 	}
-	if (found_cc && vi->cc_payload_idx < sizeof(vi->cc_payload)) {
+	if (found_cc && vi->cc_payload_idx < ARRAY_SIZE(vi->cc_payload)) {
 		vi->cc_payload[vi->cc_payload_idx++] = cc;
 		set_bit(IVTV_F_I_UPDATE_CC, &itv->i_flags);
 	}