ASoC: txx9: 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/soc.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: Mark Brown <broonie@kernel.org>

sound/soc/txx9/txx9aclc.c

@@ -271,7 +271,7 @@ static int txx9aclc_pcm_close(struct snd_pcm_substream *substream)
 	return 0;
 }
 
-static struct snd_pcm_ops txx9aclc_pcm_ops = {
+static const struct snd_pcm_ops txx9aclc_pcm_ops = {
 	.open		= txx9aclc_pcm_open,
 	.close		= txx9aclc_pcm_close,
 	.ioctl		= snd_pcm_lib_ioctl,