dt-bindings: gpio: gpio-vf610: Add imx8ulp compatible string

Add the compatible string for i.MX8ULP.
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Reviewed-by: Dong Aisheng <aisheng.dong@nxp.com>
Acked-by: Rob Herring <robh@kernel.org>
Signed-off-by: Jacky Bai <ping.bai@nxp.com>
Signed-off-by: Peng Fan <peng.fan@nxp.com>
Signed-off-by: Bartosz Golaszewski <brgl@bgdev.pl>

Documentation/devicetree/bindings/gpio/gpio-vf610.yaml

@@ -24,6 +24,9 @@ properties:
       - items:
           - const: fsl,imx7ulp-gpio
           - const: fsl,vf610-gpio
+      - items:
+          - const: fsl,imx8ulp-gpio
+          - const: fsl,imx7ulp-gpio
 
   reg:
     description: The first reg tuple represents the PORT module, the second tuple