ASoC: rsnd: control SCU ops in probe timing

SCU will be used if platform requested to use.
Current driver is checking it in runtime,
but, it can be decided in probe timing.
This patch do it

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