boards: frdm_mcxa166, frdm_mcxa276: add temperature sensor support

1. enable temperature sensor support
2. verified samples/sensor/die_temp_polling

Signed-off-by: Peter Wang <chaoyi.wang@nxp.com>

boards/nxp/frdm_mcxa166/frdm_mcxa166.dts

@@ -21,6 +21,7 @@
 		sw0 = &user_button_2;
 		sw1 = &user_button_3;
 		watchdog0 = &wwdt0;
+		die-temp0 = &temp0;
 	};
 
 	chosen {

boards/nxp/frdm_mcxa276/frdm_mcxa276.dts

@@ -23,6 +23,7 @@
 		sw1 = &user_button_3;
 		watchdog0 = &wwdt0;
 		ambient-temp0 = &p3t1755;
+		die-temp0 = &temp0;
 	};
 
 	chosen {

dts/arm/nxp/nxp_mcxa166.dtsi

@@ -308,6 +308,11 @@
 			clocks = <&syscon MCUX_LPADC1_CLK>;
 		};
 
+		temp0: temp0 {
+			compatible = "nxp,lpadc-temp40";
+			status = "disabled";
+		};
+
 		lpadc1: lpadc@400b0000 {
 			compatible = "nxp,lpc-lpadc";
 			reg = <0x400b0000 0x1000>;

dts/arm/nxp/nxp_mcxa276.dtsi

@@ -321,6 +321,11 @@
 			clocks = <&syscon MCUX_LPADC1_CLK>;
 		};
 
+		temp0: temp0 {
+			compatible = "nxp,lpadc-temp40";
+			status = "disabled";
+		};
+
 		lpadc1: lpadc@400b0000 {
 			compatible = "nxp,lpc-lpadc";
 			reg = <0x400b0000 0x1000>;

samples/sensor/die_temp_polling/boards/frdm_mcxa166.overlay

@@ -0,0 +1,26 @@
+/*
+ * Copyright 2025 NXP
+ *
+ * SPDX-License-Identifier: Apache-2.0
+ */
+#include <zephyr/dt-bindings/adc/adc.h>
+#include <zephyr/dt-bindings/adc/mcux-lpadc.h>
+
+&lpadc0 {
+	status = "okay";
+	#address-cells = <1>;
+	#size-cells = <0>;
+
+	channel@0 {
+		reg = <0>;
+		zephyr,gain = "ADC_GAIN_1";
+		zephyr,reference = "ADC_REF_EXTERNAL0";
+		zephyr,acquisition-time = <ADC_ACQ_TIME(ADC_ACQ_TIME_TICKS, 131)>;
+		zephyr,input-positive = <MCUX_LPADC_CH26A>;
+	};
+};
+
+&temp0 {
+	status = "okay";
+	io-channels = <&lpadc0 0>;
+};

samples/sensor/die_temp_polling/boards/frdm_mcxa276.overlay

@@ -0,0 +1,26 @@
+/*
+ * Copyright 2025 NXP
+ *
+ * SPDX-License-Identifier: Apache-2.0
+ */
+#include <zephyr/dt-bindings/adc/adc.h>
+#include <zephyr/dt-bindings/adc/mcux-lpadc.h>
+
+&lpadc0 {
+	status = "okay";
+	#address-cells = <1>;
+	#size-cells = <0>;
+
+	channel@0 {
+		reg = <0>;
+		zephyr,gain = "ADC_GAIN_1";
+		zephyr,reference = "ADC_REF_EXTERNAL0";
+		zephyr,acquisition-time = <ADC_ACQ_TIME(ADC_ACQ_TIME_TICKS, 131)>;
+		zephyr,input-positive = <MCUX_LPADC_CH26A>;
+	};
+};
+
+&temp0 {
+	status = "okay";
+	io-channels = <&lpadc0 0>;
+};