ALSA: pci: constify snd_kcontrol_new structures

Declare snd_kcontrol_new structures as const as they are only passed as
an argument to the function snd_ctl_new1. This argument is of type
const, so snd_kcontrol_new structures having the same property can be
made const too.
Done using Coccinelle:

@r1 disable optional_qualifier @
identifier i;
position p;
@@
static struct snd_kcontrol_new i@p = {...};

@ok1@
identifier r1.i;
position p;
expression e1;
@@
snd_ctl_new1(&i@p,e1)

@bad@
position p!={r1.p,ok1.p};
identifier r1.i;
@@
i@p

@depends on !bad disable optional_qualifier@
identifier r1.i;
@@
+const
struct snd_kcontrol_new i;

Signed-off-by: Bhumika Goyal <bhumirks@gmail.com>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
diff --git a/sound/pci/via82xx.c b/sound/pci/via82xx.c
index 2d8c14e..d078e86 100644
--- a/sound/pci/via82xx.c
+++ b/sound/pci/via82xx.c
@@ -1683,7 +1683,7 @@ static int snd_via8233_dxs3_spdif_put(struct snd_kcontrol *kcontrol,
 	return 0;
 }
 
-static struct snd_kcontrol_new snd_via8233_dxs3_spdif_control = {
+static const struct snd_kcontrol_new snd_via8233_dxs3_spdif_control = {
 	.name = SNDRV_CTL_NAME_IEC958("Output ",NONE,SWITCH),
 	.iface = SNDRV_CTL_ELEM_IFACE_MIXER,
 	.info = snd_via8233_dxs3_spdif_info,
@@ -1772,7 +1772,7 @@ static int snd_via8233_pcmdxs_volume_put(struct snd_kcontrol *kcontrol,
 
 static const DECLARE_TLV_DB_SCALE(db_scale_dxs, -4650, 150, 1);
 
-static struct snd_kcontrol_new snd_via8233_pcmdxs_volume_control = {
+static const struct snd_kcontrol_new snd_via8233_pcmdxs_volume_control = {
 	.name = "PCM Playback Volume",
 	.iface = SNDRV_CTL_ELEM_IFACE_MIXER,
 	.access = (SNDRV_CTL_ELEM_ACCESS_READWRITE |
@@ -1783,7 +1783,7 @@ static struct snd_kcontrol_new snd_via8233_pcmdxs_volume_control = {
 	.tlv = { .p = db_scale_dxs }
 };
 
-static struct snd_kcontrol_new snd_via8233_dxs_volume_control = {
+static const struct snd_kcontrol_new snd_via8233_dxs_volume_control = {
 	.iface = SNDRV_CTL_ELEM_IFACE_PCM,
 	.device = 0,
 	/* .subdevice set later */