V4L/DVB (7158): Fix em28xx audio initialization

AC97 register initialization seem to always be needed. This patch fixes audio
for Prolink/Pixelview USB2 board.

Signed-off-by: Mauro Carvalho Chehab <mchehab@infradead.org>
diff --git a/drivers/media/video/em28xx/em28xx-cards.c b/drivers/media/video/em28xx/em28xx-cards.c
index fc16077..aae7753 100644
--- a/drivers/media/video/em28xx/em28xx-cards.c
+++ b/drivers/media/video/em28xx/em28xx-cards.c
@@ -393,15 +393,15 @@
 		.input          = { {
 			.type     = EM28XX_VMUX_TELEVISION,
 			.vmux     = SAA7115_COMPOSITE2,
-			.amux     = 1,
+			.amux     = EM28XX_AMUX_LINE_IN,
 		}, {
 			.type     = EM28XX_VMUX_COMPOSITE1,
 			.vmux     = SAA7115_COMPOSITE0,
-			.amux     = 1,
+			.amux     = EM28XX_AMUX_LINE_IN,
 		}, {
 			.type     = EM28XX_VMUX_SVIDEO,
 			.vmux     = SAA7115_SVIDEO3,
-			.amux     = 1,
+			.amux     = EM28XX_AMUX_LINE_IN,
 		} },
 	},
 };