ASoC: fsl_spdif: constify snd_soc_dai_ops structure

This structure is only stored in the ops field of a snd_soc_dai_driver
structure. That field is declared const, so snd_soc_dai_ops structures
that have this property can be declared as const also.
Signed-off-by: Gustavo A. R. Silva <garsilva@embeddedor.com>
Signed-off-by: Mark Brown <broonie@kernel.org>

sound/soc/fsl/fsl_spdif.c

@@ -626,7 +626,7 @@ static int fsl_spdif_trigger(struct snd_pcm_substream *substream,
 	return 0;
 }
 
-static struct snd_soc_dai_ops fsl_spdif_dai_ops = {
+static const struct snd_soc_dai_ops fsl_spdif_dai_ops = {
 	.startup = fsl_spdif_startup,
 	.hw_params = fsl_spdif_hw_params,
 	.trigger = fsl_spdif_trigger,