ASoC: intel/boards: use asoc_substream_to_rtd()

Now we can use asoc_substream_to_rtd() macro,
let's use it.

Signed-off-by: Kuninori Morimoto <kuninori.morimoto.gx@renesas.com>
Reviewed-by: Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com>
Link: https://lore.kernel.org/r/87v9i9yddc.wl-kuninori.morimoto.gx@renesas.com
Signed-off-by: Mark Brown <broonie@kernel.org>

sound/soc/intel/boards/haswell.c

@@ -55,7 +55,7 @@ static int haswell_ssp0_fixup(struct snd_soc_pcm_runtime *rtd,
 static int haswell_rt5640_hw_params(struct snd_pcm_substream *substream,
 	struct snd_pcm_hw_params *params)
 {
-	struct snd_soc_pcm_runtime *rtd = substream->private_data;
+	struct snd_soc_pcm_runtime *rtd = asoc_substream_to_rtd(substream);
 	struct snd_soc_dai *codec_dai = asoc_rtd_to_codec(rtd, 0);
 	int ret;