ALSA: aoa: Constify snd_device_ops definitions

Now we may declare const for snd_device_ops definitions, so let's do
it for optimization.

There should be no functional changes by this patch.

Link: https://lore.kernel.org/r/[e-mail]
Signed-off-by: Takashi Iwai <[e-mail]>

sound/aoa/aoa.h

···
 };
         
 extern int aoa_snd_device_new(enum snd_device_type type,
-	void * device_data, struct snd_device_ops * ops);
+	void *device_data, const struct snd_device_ops *ops);
 extern struct snd_card *aoa_get_card(void);
 extern int aoa_snd_ctl_add(struct snd_kcontrol* control);
 

sound/aoa/codecs/onyx.c

···
 	return 0;
 }
 
-static struct snd_device_ops ops = {
+static const struct snd_device_ops ops = {
 	.dev_register = onyx_dev_register,
 };
 

sound/aoa/codecs/tas.c

···
 	return 0;
 }
 
-static struct snd_device_ops ops = {
+static const struct snd_device_ops ops = {
 	.dev_register = tas_dev_register,
 };
 

sound/aoa/codecs/toonie.c

···
 	return 0;
 }
 
-static struct snd_device_ops ops = {
+static const struct snd_device_ops ops = {
 	.dev_register = toonie_dev_register,
 };
 

sound/aoa/core/alsa.c

···
 }
 
 int aoa_snd_device_new(enum snd_device_type type,
-		       void * device_data, struct snd_device_ops * ops)
+		       void *device_data, const struct snd_device_ops *ops)
 {
 	struct snd_card *card = aoa_get_card();
 	int err;