ASoC: wm8961: add support for devicetree

Add support for devicetree to the WM8961 driver so it can be used with
modern DT-based kernels.

Signed-off-by: Doug Brown <doug@schmorgal.com>
Acked-by: Charles Keepax <ckeepax@opensource.cirrus.com>
Link: https://lore.kernel.org/r/20221003032414.248326-3-doug@schmorgal.com


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