dt-bindings: display: enable port jdi,lt070me05000

Enable port inside panel bindings.

Fixes warnings generated by `make qcom-apq8064-asus-nexus7-flo.dtb` as:
arch/arm/boot/dts/qcom-apq8064-asus-nexus7-flo.dt.yaml: panel@0: 'port' does not match any of the regexes: 'pinctrl-[0-9]+'
From schema: Documentation/devicetree/bindings/display/panel/jdi,lt070me05000.yaml

Signed-off-by: David Heidelberg <[e-mail]>
Signed-off-by: Rob Herring <[e-mail]>
Link: https://lore.kernel.org/r/[e-mail]

Documentation/devicetree/bindings/display/panel/jdi,lt070me05000.yaml

···
       phandle of the gpio for power ic line
       Power IC supply enable, High active
 
+  port: true
+
 required:
   - compatible
   - reg