[ALSA] oxygen: add front panel controls

Add mixer controls for the front panel AC97 codec.

Signed-off-by: Clemens Ladisch <clemens@ladisch.de>
Signed-off-by: Jaroslav Kysela <perex@perex.cz>
diff --git a/sound/pci/oxygen/virtuoso.c b/sound/pci/oxygen/virtuoso.c
index 23bfab4..2e1a699 100644
--- a/sound/pci/oxygen/virtuoso.c
+++ b/sound/pci/oxygen/virtuoso.c
@@ -247,9 +247,11 @@
 	}
 }
 
-static void xonar_ac97_switch_hook(struct oxygen *chip,
+static void xonar_ac97_switch_hook(struct oxygen *chip, unsigned int codec,
 				   unsigned int reg, int mute)
 {
+	if (codec != 0)
+		return;
 	/* line-in is exclusive */
 	switch (reg) {
 	case AC97_LINE: