ASoC: madera: Read device tree configuration

Read the configuration of the Madera ASoC driver from device tree.

Signed-off-by: Charles Keepax <ckeepax@opensource.cirrus.com>
Link: https://lore.kernel.org/r/20190722135209.30302-1-ckeepax@opensource.cirrus.com


Signed-off-by: Mark Brown <broonie@kernel.org>