Add the DT binding documention of the internal DAC found in the Amlogic
gxl, g12a and sm1 SoC family.
Signed-off-by: Jerome Brunet <jbrunet@baylibre.com>
Link: https://lore.kernel.org/r/20200219173503.1112561-2-jbrunet@baylibre.comSigned-off-by: Mark Brown <broonie@kernel.org>