ASoC: don't use original dummy dlc

Merge series from Kuninori Morimoto <kuninori.morimoto.gx@renesas.com>:

"Empty" dlc might be used on Platform, but "dummy" dlc is not needed
for it. [PATCH 1/5][PATCH 2/5] removes "dummy" dlc from Platform.

Now ASoC have common dummy dlc (= snd_soc_dummy_dlc).
[PATCH 3/5][PATCH 4/5] will use it instead of original dummy dlc.

Many drivers are using below macro

	SND_SOC_DAILINK_DEFS(link,
		     DAILINK_COMP_ARRAY(COMP_CPU(...)),
(X)		     DAILINK_COMP_ARRAY(COMP_DUMMY()),
		     DAILINK_COMP_ARRAY(COMP_EMPTY()));

But (X) part will create original dummy dlc.
[PATCH 5/5] will try not to create original dummy dlc, and replace
it to common dummy dlc.