[media] si2157: Add support for spectral inversion

This is needed for PCTV 522e support.

Signed-off-by: Matthias Schwarzott <zzam@gentoo.org>
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 4465c46..6da4d5d 100644
--- a/drivers/media/tuners/si2157.h
+++ b/drivers/media/tuners/si2157.h
@@ -29,6 +29,11 @@
 	 * frontend
 	 */
 	struct dvb_frontend *fe;
+
+	/*
+	 * Spectral Inversion
+	 */
+	bool inversion;
 };
 
 #endif