dt-bindings: fpga: zynq: convert bindings to YAML

Convert FPGA for Xilinx Zynq SoC bindings documentation to YAML.

Signed-off-by: Nobuhiro Iwamatsu <iwamatsu@nigauri.org>
Link: https://lore.kernel.org/r/20210613212856.296153-1-iwamatsu@nigauri.org


Signed-off-by: Rob Herring <robh@kernel.org>