dt-bindings: qcom,pmic-gpio: Add pm2250 compatible string

Add compatible strings for pm2250 SPMI GPIO to documentation.
Signed-off-by: NLoic Poulain <loic.poulain@linaro.org>
Link: https://lore.kernel.org/r/1637076915-3280-2-git-send-email-loic.poulain@linaro.orgSigned-off-by: NLinus Walleij <linus.walleij@linaro.org>

Documentation/devicetree/bindings/pinctrl/qcom,pmic-gpio.yaml

@@ -17,6 +17,7 @@ properties:
   compatible:
     items:
       - enum:
+          - qcom,pm2250-gpio
           - qcom,pm660-gpio
           - qcom,pm660l-gpio
           - qcom,pm6150-gpio