dt-bindings: mfd: cirrus,madera: Fix 'interrupts' in example

The 'interrupts' properties takes an irq number, not a phandle, and
'interrupt-parent' isn't needed in examples.

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

Documentation/devicetree/bindings/mfd/cirrus,madera.yaml

···
 
             interrupt-controller;
             #interrupt-cells = <2>;
-            interrupts = <&host_irq1>;
-            interrupt-parent = <&gic>;
+            interrupts = <4 1 0>;
 
             gpio-controller;
             #gpio-cells = <2>;