New bindings (using a syscon) are available for AP806 and CP110
compatibles. Add a reference to these files from the original
documentation.

Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com>
Acked-by: Rob Herring <robh@kernel.org>
Signed-off-by: Eduardo Valentin <edubezval@gmail.com>