ALSA: arm: constify snd_pcm_ops structures

snd_pcm_ops are not supposed to change at runtime. All functions
working with snd_pcm_ops provided by <sound/pcm.h> work with
const snd_pcm_ops. So mark the non-const structs as const.
Signed-off-by: Arvind Yadav <arvind.yadav.cs@gmail.com>
Signed-off-by: Takashi Iwai <tiwai@suse.de>

sound/arm/aaci.c

@@ -635,7 +635,7 @@ static int aaci_pcm_playback_trigger(struct snd_pcm_substream *substream, int cm
 	return ret;
 }
 
-static struct snd_pcm_ops aaci_playback_ops = {
+static const struct snd_pcm_ops aaci_playback_ops = {
 	.open		= aaci_pcm_open,
 	.close		= aaci_pcm_close,
 	.ioctl		= snd_pcm_lib_ioctl,
@@ -738,7 +738,7 @@ static int aaci_pcm_capture_prepare(struct snd_pcm_substream *substream)
 	return 0;
 }
 
-static struct snd_pcm_ops aaci_capture_ops = {
+static const struct snd_pcm_ops aaci_capture_ops = {
 	.open		= aaci_pcm_open,
 	.close		= aaci_pcm_close,
 	.ioctl		= snd_pcm_lib_ioctl,

sound/arm/pxa2xx-pcm.c

@@ -68,7 +68,7 @@ static int pxa2xx_pcm_close(struct snd_pcm_substream *substream)
 	return __pxa2xx_pcm_close(substream);
 }
 
-static struct snd_pcm_ops pxa2xx_pcm_ops = {
+static const struct snd_pcm_ops pxa2xx_pcm_ops = {
 	.open		= pxa2xx_pcm_open,
 	.close		= pxa2xx_pcm_close,
 	.ioctl		= snd_pcm_lib_ioctl,