feat(u0): add STM32U0xx support

Signed-off-by: Frederic Pillon <frederic.pillon@st.com>

Author: fpistm

src/rtc.c

@@ -1194,8 +1194,8 @@ void RTC_Alarm_IRQHandler(void)
 #if defined(STM32F071xB) || defined(STM32F072xB) || defined(STM32F078xx) || \
     defined(STM32F091xC) || defined(STM32F098xx) || defined(STM32F070xB) || \
     defined(STM32F030xC) || defined(STM32G0xx) || defined(STM32H5xx) || \
-    defined(STM32L0xx) || defined(STM32L5xx) || defined(STM32U5xx) || \
-    defined(STM32WBAxx)
+    defined(STM32L0xx) || defined(STM32L5xx) || defined(STM32U0xx) ||\
+    defined(STM32U5xx) || defined(STM32WBAxx)
   // In some cases, the same vector is used to manage WakeupTimer,
   // but with a dedicated HAL IRQHandler
   HAL_RTCEx_WakeUpTimerIRQHandler(&RtcHandle);

src/rtc.h

@@ -134,7 +134,7 @@ typedef void(*voidCallbackPtr)(void *);
 #define RTC_Alarm_IRQn RTC_IRQn
 #define RTC_Alarm_IRQHandler RTC_IRQHandler
 #endif
-#if defined(STM32G0xx)
+#if defined(STM32G0xx) || defined(STM32U0xx)
 #define RTC_Alarm_IRQn RTC_TAMP_IRQn
 #define RTC_Alarm_IRQHandler RTC_TAMP_IRQHandler
 #endif
@@ -148,7 +148,7 @@ typedef void(*voidCallbackPtr)(void *);
 #elif defined(STM32MP1xx)
 // global RTC interrupt
 #define ONESECOND_IRQn RTC_WKUP_ALARM_IRQn
-#elif defined(STM32G0xx)
+#elif defined(STM32G0xx) || defined(STM32U0xx)
 // global RTC/TAMP interrupt
 #define ONESECOND_IRQn RTC_TAMP_IRQn
 #elif defined(CORE_CM0PLUS) && \