ASoC: core: Add extra dapm properties for Device Tree

The current helper functions, snd_soc_of_parse_audio_simple_widgets()
and snd_soc_of_parse_audio_routing(), set dapm_widgets and dapm_routes
without caring if they are already set by using build-in widgets and
routes in the card driver. So there could be one of them, build-in one
or Device Tree one, overrided by the other depending on which one was
assigned later.

This patch adds an extra pair of dapm_widgets and dapm_routes for DT
use only so as to prevent unexpected overriding.

Signed-off-by: Nicolin Chen <nicoleotsuka@gmail.com>
Signed-off-by: Mark Brown <broonie@kernel.org>