ASoC: rsnd: update Audio DMA path search method

ASoC: rsnd: update Audio DMA path search method

Current rsnd driver is assuming Audio DMAC / Audio DMAC peri peri
are used from SSI/SSIU/SRC/DVC. But we will add CTU/MIX to this driver.
Then, current DMA path searching method is not understandable, and good
enough for this purpose. This patch update DMA path search method, more
simply.

Signed-off-by: Kuninori Morimoto <kuninori.morimoto.gx@renesas.com>
Tested-by: Keita Kobayashi <keita.kobayashi.ym@renesas.com>
Signed-off-by: Mark Brown <broonie@kernel.org>