boards: nordic: nrf54h20dk: enable 802.15.4 IPC by default

Enable hardware necessary for 802.15.4 IPC on nRF54H20 DK by default.

Signed-off-by: Jędrzej Ciupis <jedrzej.ciupis@nordicsemi.no>
diff --git a/boards/nordic/nrf54h20dk/nrf54h20dk_nrf54h20_cpuapp.dts b/boards/nordic/nrf54h20dk/nrf54h20dk_nrf54h20_cpuapp.dts
index 22877e4..476c076 100644
--- a/boards/nordic/nrf54h20dk/nrf54h20dk_nrf54h20_cpuapp.dts
+++ b/boards/nordic/nrf54h20dk/nrf54h20dk_nrf54h20_cpuapp.dts
@@ -26,6 +26,7 @@
 		zephyr,shell-uart = &uart136;
 		zephyr,ieee802154 = &cpuapp_ieee802154;
 		zephyr,bt-hci-ipc = &ipc0;
+		nordic,802154-spinel-ipc = &ipc0;
 	};
 
 	aliases {
diff --git a/boards/nordic/nrf54h20dk/nrf54h20dk_nrf54h20_cpurad.dts b/boards/nordic/nrf54h20dk/nrf54h20dk_nrf54h20_cpurad.dts
index dba929c..20109b6 100644
--- a/boards/nordic/nrf54h20dk/nrf54h20dk_nrf54h20_cpurad.dts
+++ b/boards/nordic/nrf54h20dk/nrf54h20dk_nrf54h20_cpurad.dts
@@ -27,6 +27,7 @@
 		zephyr,shell-uart = &uart135;
 		zephyr,ieee802154 = &cpurad_ieee802154;
 		zephyr,bt-hci-ipc = &ipc0;
+		nordic,802154-spinel-ipc = &ipc0;
 	};
 };