Merge pull request #3617 from ifreecoding/debug

局部变量tm_new未初始化，该结构体变量中的tm_isdst值为栈中残留值，不确定，该值会影响是否使用夏令时，最终表现概率性使用夏令时，…

bsp/stm32/libraries/HAL_Drivers/drv_rtc.c

@@ -40,7 +40,7 @@ static time_t get_rtc_timestamp(void)
 {
     RTC_TimeTypeDef RTC_TimeStruct = {0};
     RTC_DateTypeDef RTC_DateStruct = {0};
-    struct tm tm_new;
+    struct tm tm_new = {0};
 
     HAL_RTC_GetTime(&RTC_Handler, &RTC_TimeStruct, RTC_FORMAT_BIN);
     HAL_RTC_GetDate(&RTC_Handler, &RTC_DateStruct, RTC_FORMAT_BIN);