dts: bindings: gpio: nrf-gpiote: Extend description

Add new feature flags to gpiote node.
Include pinctrl. Pins used by GPIOTE0 on nrf54h20/cpurad require CTRLSEL
configuration. Pins are listed using pinctrl and parsed by nrf-regtool
to prepare UICR configuration.

Signed-off-by: Krzysztof Chruściński <krzysztof.chruscinski@nordicsemi.no>

Author: nordic-krch

dts/bindings/gpio/nordic,nrf-gpiote.yaml

@@ -8,6 +8,7 @@ compatible: "nordic,nrf-gpiote"
 include:
   - base.yaml
   - nordic,split-channels.yaml
+  - pinctrl-device.yaml
 
 properties:
   reg:
@@ -16,6 +17,17 @@ properties:
   interrupts:
     required: true
 
+  no-port-event:
+    type: boolean
+    description: |
+      Indicates that the GPIOTE instance does not support PORT event.
+
+  fixed-channels-supported:
+    type: boolean
+    description: |
+      Indicates that the GPIOTE instance has fixed connection between pins and TE channels.
+      It means that a specific TE channel must be used for a given pin.
+
   instance:
     type: int
     required: true