ASoC: bindings: wm8960: Add property for headphone detection

Add two properties for headphone detection.

wlf,hp-cfg: A list of headphone jack detect configuration register values
wlf,gpio-cfg: A list of GPIO configuration register values

Signed-off-by: Shengjiu Wang <shengjiu.wang@nxp.com>
Reviewed-by: Rob Herring <robh@kernel.org>
Link: https://lore.kernel.org/r/1591180013-12416-1-git-send-email-shengjiu.wang@nxp.com


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