ASoC: audio-graph-card: cleanup DAI link loop method - step1

Current audio-graph-card is parsing DAI link for both "normal sound" and
"DPCM sound". On this driver, it needs to count and parse
DAIs/Links/Codec Conf from each links.
Then, counting/parsing link loop are very similar, but using different
implementation. Because of this background, the link loop code is very
mysterious. Mystery code will be trouble in the future.

This patch adds/modifies counting and parsing function for
"normal sound" and "DPCM sound", and call it from link loop.
This is prepare for cleanup DAI link loop method.

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