ASoC: simple-card: add asoc_simple_card_parse_daifmt()

Current daifmt setting method in simple-card driver is
placed to many places, and using un-readable/confusable method.
This patch adds new asoc_simple_card_parse_daifmt()
and tidyup code.

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