ASoC: add new simple-card-utils.c

Current ALSA SoC has simple-card driver which is supporting both
platform and DT probe.
Now, some sound cards driver are created based on simple-card.
They have similar feature or function, but implemented separately
on each drivers. This is a waste of code.
OTOH, merging these driver into same driver is highly risk,
because it will be very difficult to keep compatibility.
More over, ALSA SoC want to have graph base of DT feature in the
future. Maybe it want to use simple-card like feature / function.
Because of these background, this patch creates simple-card
helper utils, and provides common function to each drivers.
1st is asoc_simple_card_parse_daifmt()

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

sound/soc/generic/Kconfig

@@ -1,3 +1,6 @@
+config SND_SIMPLE_CARD_UTILS
+       tristate
+
 config SND_SIMPLE_CARD
 	tristate "ASoC Simple sound card support"
 	help