[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/cs4281.c b/sound/pci/cs4281.c
index 8e5519d..44cf546 100644
--- a/sound/pci/cs4281.c
+++ b/sound/pci/cs4281.c
@@ -1055,7 +1055,7 @@
 	return change;
 }
 
-static DECLARE_TLV_DB_SCALE(db_scale_dsp, -4650, 150, 0);
+static const DECLARE_TLV_DB_SCALE(db_scale_dsp, -4650, 150, 0);
 
 static struct snd_kcontrol_new snd_cs4281_fm_vol = 
 {