dts: arm: st: wb0: add IWDG node to STM32WB0 series

Add a node for the Independent Watchdog to STM32WB0 series DTSI.

Signed-off-by: Mathieu Choplain <mathieu.choplain@st.com>

dts/arm/st/wb0/stm32wb0.dtsi

diff --git a/dts/arm/st/wb0/stm32wb0.dtsi b/dts/arm/st/wb0/stm32wb0.dtsi
index 49d29e3..0900f8f 100644
--- a/dts/arm/st/wb0/stm32wb0.dtsi
+++ b/dts/arm/st/wb0/stm32wb0.dtsi
@@ -283,6 +283,13 @@
 			generation-delay-ns = <1250>; /* 1.25us */
 			status = "disabled";
 		};
+
+		iwdg: watchdog@40003000 {
+			compatible = "st,stm32-watchdog";
+			reg = <0x40003000 DT_SIZE_K(1)>;
+			clocks = <&rcc STM32_CLOCK(APB0, 14)>;
+			status = "disabled";
+		};
 	};
 
 	bt_hci_wb0: bt_hci_wb0 {