ASoC: remove snd_soc_pcm_set/get_drvdata()

snd_soc_pcm_set_drvdata() will set driver data to rtd->dev,
but driver data of rtd->dev is already used as "rtd" on
soc_post_component_init().

	static int soc_post_component_init(xxx)
	{
		...
		dev_set_drvdata(rtd->dev, rtd);
		...
	}

To remove confusion, this patch removes snd_soc_pcm_set/get_drvdata().

Signed-off-by: Kuninori Morimoto <kuninori.morimoto.gx@renesas.com>
Signed-off-by: Mark Brown <broonie@kernel.org>