ALSA: intel8x0: 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>
diff --git a/sound/pci/intel8x0.c b/sound/pci/intel8x0.c
index 6d17b17..a8d7092 100644
--- a/sound/pci/intel8x0.c
+++ b/sound/pci/intel8x0.c
@@ -1136,31 +1136,31 @@
 	.fifo_size =		0,
 };
 
-static unsigned int channels4[] = {
+static const unsigned int channels4[] = {
 	2, 4,
 };
 
-static struct snd_pcm_hw_constraint_list hw_constraints_channels4 = {
+static const struct snd_pcm_hw_constraint_list hw_constraints_channels4 = {
 	.count = ARRAY_SIZE(channels4),
 	.list = channels4,
 	.mask = 0,
 };
 
-static unsigned int channels6[] = {
+static const unsigned int channels6[] = {
 	2, 4, 6,
 };
 
-static struct snd_pcm_hw_constraint_list hw_constraints_channels6 = {
+static const struct snd_pcm_hw_constraint_list hw_constraints_channels6 = {
 	.count = ARRAY_SIZE(channels6),
 	.list = channels6,
 	.mask = 0,
 };
 
-static unsigned int channels8[] = {
+static const unsigned int channels8[] = {
 	2, 4, 6, 8,
 };
 
-static struct snd_pcm_hw_constraint_list hw_constraints_channels8 = {
+static const struct snd_pcm_hw_constraint_list hw_constraints_channels8 = {
 	.count = ARRAY_SIZE(channels8),
 	.list = channels8,
 	.mask = 0,