arch/arm/boot/dts/zynq-zc706-adv7511-ad9683-ebz: Add device tree

Signed-off-by: Michael Hennerich <michael.hennerich@analog.com>
iio: adc: cf_axi_adc: Add support for AD9683

Signed-off-by: Michael Hennerich <michael.hennerich@analog.com>