ALSA: ppc: 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/ppc/pmac.c

@@ -681,7 +681,7 @@ static int snd_pmac_capture_close(struct snd_pcm_substream *subs)
 /*
  */
 
-static struct snd_pcm_ops snd_pmac_playback_ops = {
+static const struct snd_pcm_ops snd_pmac_playback_ops = {
 	.open =		snd_pmac_playback_open,
 	.close =	snd_pmac_playback_close,
 	.ioctl =	snd_pcm_lib_ioctl,
@@ -692,7 +692,7 @@ static struct snd_pcm_ops snd_pmac_playback_ops = {
 	.pointer =	snd_pmac_playback_pointer,
 };
 
-static struct snd_pcm_ops snd_pmac_capture_ops = {
+static const struct snd_pcm_ops snd_pmac_capture_ops = {
 	.open =		snd_pmac_capture_open,
 	.close =	snd_pmac_capture_close,
 	.ioctl =	snd_pcm_lib_ioctl,

sound/ppc/snd_ps3.c

@@ -772,7 +772,7 @@ static struct snd_kcontrol_new spdif_ctls[] = {
 	},
 };
 
-static struct snd_pcm_ops snd_ps3_pcm_spdif_ops = {
+static const struct snd_pcm_ops snd_ps3_pcm_spdif_ops = {
 	.open = snd_ps3_pcm_open,
 	.close = snd_ps3_pcm_close,
 	.ioctl = snd_pcm_lib_ioctl,