dts: arm: st: u0: add adc node in dtsi file

all stm32u0 boards have only one and same
adc peripheral.

Signed-off-by: Fabrice DJIATSA <fabrice.djiatsa-ext@st.com>

dts/arm/st/u0/stm32u0.dtsi

@@ -8,6 +8,8 @@
 #include <arm/armv6-m.dtsi>
 #include <zephyr/dt-bindings/clock/stm32u0_clock.h>
 #include <zephyr/dt-bindings/gpio/gpio.h>
+#include <zephyr/dt-bindings/adc/adc.h>
+#include <zephyr/dt-bindings/adc/stm32l4_adc.h>
 #include <zephyr/dt-bindings/pwm/pwm.h>
 #include <zephyr/dt-bindings/pwm/stm32_pwm.h>
 #include <zephyr/dt-bindings/i2c/i2c.h>
@@ -211,6 +213,22 @@
  status = "disabled";
  };
 
+ adc1: adc@40012400 {
+ compatible = "st,stm32-adc";
+ reg = <0x40012400 0x400>;
+ clocks = <&rcc STM32_CLOCK_BUS_APB1_2 0x00100000>;
+ interrupts = <12 0>;
+ status = "disabled";
+ #io-channel-cells = <1>;
+ resolutions = <STM32_ADC_RES(12, 0x00)
+ STM32_ADC_RES(10, 0x01)
+ STM32_ADC_RES(8, 0x02)
+ STM32_ADC_RES(6, 0x03)>;
+ sampling-times = <2 4 8 13 20 40 80 161>;
+ num-sampling-time-common-channels = <2>;
+ st,adc-sequencer = <NOT_FULLY_CONFIGURABLE>;
+ };
+
  dac1: dac@40007400 {
  compatible = "st,stm32-dac";
  reg = <0x40007400 0x400>;