[ALSA] Add even more 'const' to everything related to TLV

Mark TLV data as 'const'
Signed-of-by: Philipp Matthias Hahn <pmhahn@pmhahn.de>

Signed-off-by: Takashi Iwai <tiwai@suse.de>
Signed-off-by: Jaroslav Kysela <perex@suse.cz>
diff --git a/sound/pci/ice1712/ice1712.c b/sound/pci/ice1712/ice1712.c
index b8baadb..830a1bb 100644
--- a/sound/pci/ice1712/ice1712.c
+++ b/sound/pci/ice1712/ice1712.c
@@ -1378,7 +1378,7 @@
 	return change;
 }
 
-static DECLARE_TLV_DB_SCALE(db_scale_playback, -14400, 150, 0);
+static const DECLARE_TLV_DB_SCALE(db_scale_playback, -14400, 150, 0);
 
 static const struct snd_kcontrol_new snd_ice1712_multi_playback_ctrls[] __devinitdata = {
 	{