dt-bindings: arm: ux500: Document samsung,golden compatible

The Samsung Galaxy S III mini ("samsung-golden") can now boot
mainline Linux; document the samsung,golden compatible that is
used in its device tree.
Signed-off-by: Stephan Gerhold <stephan@gerhold.net>
Link: https://lore.kernel.org/r/20191219202052.19039-4-stephan@gerhold.netSigned-off-by: Linus Walleij <linus.walleij@linaro.org>

Documentation/devicetree/bindings/arm/ux500.yaml

@@ -29,3 +29,8 @@ properties:
         items:
           - const: calaosystems,snowball-a9500
           - const: st-ericsson,u9500
+
+      - description: Samsung Galaxy S III mini (GT-I8190)
+        items:
+          - const: samsung,golden
+          - const: st-ericsson,u8500