ALSA: cs423x: Constify hw_constraints

snd_pcm_hw_constraint_list(), *_ratnums() and *_ratdens() receive the
const pointers.  Constify the corresponding static objects for better
hardening.
Signed-off-by: Takashi Iwai <tiwai@suse.de>

sound/isa/cs423x/cs4236_lib.c

@@ -138,7 +138,7 @@ static unsigned char snd_cs4236_ctrl_in(struct snd_wss *chip, unsigned char reg)
 
 #define CLOCKS 8
 
-static struct snd_ratnum clocks[CLOCKS] = {
+static const struct snd_ratnum clocks[CLOCKS] = {
 	{ .num = 16934400, .den_min = 353, .den_max = 353, .den_step = 1 },
 	{ .num = 16934400, .den_min = 529, .den_max = 529, .den_step = 1 },
 	{ .num = 16934400, .den_min = 617, .den_max = 617, .den_step = 1 },
@@ -149,7 +149,7 @@ static struct snd_ratnum clocks[CLOCKS] = {
 	{ .num = 16934400/16, .den_min = 21, .den_max = 192, .den_step = 1 }
 };
 
-static struct snd_pcm_hw_constraint_ratnums hw_constraints_clocks = {
+static const struct snd_pcm_hw_constraint_ratnums hw_constraints_clocks = {
 	.nrats = CLOCKS,
 	.rats = clocks,
 };