dt-bindings: pinctrl: add #interrupt-cells to apple,pinctrl

The GPIO/pinctrl hardware can act as an interrupt-controller, so add
the #interrupt-cells property to the binding.

Signed-off-by: Joey Gouly <joey.gouly@arm.com>
Reviewed-by: Sven Peter <sven@svenpeter.dev>
Acked-by: Rob Herring <robh@kernel.org>
Link: https://lore.kernel.org/r/20211026175815.52703-3-joey.gouly@arm.com
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>

Author: jgouly

Documentation/devicetree/bindings/pinctrl/apple,pinctrl.yaml

@@ -43,6 +43,9 @@ properties:
 
   interrupt-controller: true
 
+  '#interrupt-cells':
+    const: 2
+
 patternProperties:
   '-pins$':
     type: object
@@ -88,6 +91,7 @@ examples:
         gpio-ranges = <&pinctrl 0 0 212>;
 
         interrupt-controller;
+        #interrupt-cells = <2>;
         interrupt-parent = <&aic>;
         interrupts = <AIC_IRQ 16 IRQ_TYPE_LEVEL_HIGH>,
                      <AIC_IRQ 17 IRQ_TYPE_LEVEL_HIGH>,