dt-bindings: usb: convert fcs,fusb302.txt to yaml

Convert fcs,fusb302.txt to yaml.

Changed:
  Add vbus-supply property

Signed-off-by: Johan Jonker <jbx6244@gmail.com>
Reviewed-by: Rob Herring <robh@kernel.org>
Link: https://lore.kernel.org/r/0336a3c4-4a43-c983-11d7-e2ae16187fc8@gmail.com


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