ALSA: hda - Use amp cache for SPDIF mute controls in patch_sigmatel.c

The amp switch of SPDIF outputs have to be cached in the amp cache
instead of codec cache.  Otherwise it conflicts with the IEC958
playback switch control in hda_codec.c.

Signed-off-by: Takashi Iwai <tiwai@suse.de>
diff --git a/sound/pci/hda/patch_sigmatel.c b/sound/pci/hda/patch_sigmatel.c
index 33170a2..068a77a 100644
--- a/sound/pci/hda/patch_sigmatel.c
+++ b/sound/pci/hda/patch_sigmatel.c
@@ -590,12 +590,12 @@
 		else
 			nid = codec->slave_dig_outs[smux_idx - 1];
 		if (spec->cur_smux[smux_idx] == smux->num_items - 1)
-			val = AMP_OUT_MUTE;
+			val = HDA_AMP_MUTE;
 		else
-			val = AMP_OUT_UNMUTE;
+			val = 0;
 		/* un/mute SPDIF out */
-		snd_hda_codec_write_cache(codec, nid, 0,
-			AC_VERB_SET_AMP_GAIN_MUTE, val);
+		snd_hda_codec_amp_stereo(codec, nid, HDA_OUTPUT, 0,
+					 HDA_AMP_MUTE, val);
 	}
 	return 0;
 }