ASoC: rsnd: fixup pcm_new callback method

bff58ea4f43d9b4a9fd6fb05fabc8f50f68131f5
(ASoC: rsnd: add DVC support) added DVC support,
and it added pcm_new callback feature for it.
Then it called all DAI's pcm_new callback, and it was wrong.
This patch fixup it and call correct callback.

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