dts: arm/nxp/mcxn23x: Add vref node for NXP MCXN23x

Add the vref node for NXP MCXN23x

Signed-off-by: Neil Chen <cheng.chen_1@nxp.com>

dts/arm/nxp/nxp_mcxn23x_common.dtsi

diff --git a/dts/arm/nxp/nxp_mcxn23x_common.dtsi b/dts/arm/nxp/nxp_mcxn23x_common.dtsi
index 4d8c199..e0bfe4a 100644
--- a/dts/arm/nxp/nxp_mcxn23x_common.dtsi
+++ b/dts/arm/nxp/nxp_mcxn23x_common.dtsi
@@ -676,6 +676,18 @@
 		input = <0>;
 		prescale = <0>;
 	};
+
+	vref: vref@111000 {
+		compatible = "nxp,vref";
+		regulator-name = "mcxn23x-vref";
+		reg = <0x111000 0x14>;
+		status = "disabled";
+		#nxp,reference-cells = <1>;
+		nxp,buffer-startup-delay-us = <400>;
+		nxp,bandgap-startup-time-us = <20>;
+		regulator-min-microvolt = <1000000>;
+		regulator-max-microvolt = <2100000>;
+	};
 };
 
 &systick {