ASoC: zx-tdm: 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/zte/zx-tdm.c

@@ -309,7 +309,7 @@ static void zx_tdm_shutdown(struct snd_pcm_substream *substream,
 	clk_disable_unprepare(zx_tdm->dai_wclk);
 }
 
-static struct snd_soc_dai_ops zx_tdm_dai_ops = {
+static const struct snd_soc_dai_ops zx_tdm_dai_ops = {
 	.trigger	= zx_tdm_trigger,
 	.hw_params	= zx_tdm_hw_params,
 	.set_fmt	= zx_tdm_set_fmt,