[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/prodigy192.c b/sound/pci/ice1712/prodigy192.c
index d551e71..31cc66e 100644
--- a/sound/pci/ice1712/prodigy192.c
+++ b/sound/pci/ice1712/prodigy192.c
@@ -357,8 +357,8 @@
 }
 #endif
 
-static DECLARE_TLV_DB_SCALE(db_scale_dac, -19125, 75, 0);
-static DECLARE_TLV_DB_SCALE(db_scale_adc, 0, 150, 0);
+static const DECLARE_TLV_DB_SCALE(db_scale_dac, -19125, 75, 0);
+static const DECLARE_TLV_DB_SCALE(db_scale_adc, 0, 150, 0);
 
 /*
  * mixers