[media] si2157: Add support for Si2158 chip

Add support for Si2158 A20 chip.

Signed-off-by: Olli Salonen <olli.salonen@iki.fi>
Reviewed-by: Antti Palosaari <crope@iki.fi>
Signed-off-by: Antti Palosaari <crope@iki.fi>
Signed-off-by: Mauro Carvalho Chehab <m.chehab@samsung.com>
diff --git a/drivers/media/tuners/si2157.h b/drivers/media/tuners/si2157.h
index f469a09..4465c46 100644
--- a/drivers/media/tuners/si2157.h
+++ b/drivers/media/tuners/si2157.h
@@ -1,5 +1,5 @@
 /*
- * Silicon Labs Si2157 silicon tuner driver
+ * Silicon Labs Si2157/2158 silicon tuner driver
  *
  * Copyright (C) 2014 Antti Palosaari <crope@iki.fi>
  *