ALSA: aaci: constify ac97_pcm structures

ac97_pcm are not supposed to change at runtime. All functions
working with ac97_pcm provided by <sound/ac97_codec.h> work with
const ac97_pcm. 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

@@ -786,7 +786,7 @@ static SIMPLE_DEV_PM_OPS(aaci_dev_pm_ops, aaci_suspend, aaci_resume);
 #endif
 
 
-static struct ac97_pcm ac97_defs[] = {
+static const struct ac97_pcm ac97_defs[] = {
 	[0] = {	/* Front PCM */
 		.exclusive = 1,
 		.r = {