Import YEEP-144 library 1.2 sources

Source-only snapshot of the 1.2 release. Drivers/ (the vendored ST HAL and
CMSIS) is excluded at 173 MB; fetch it from STMicroelectronics/STM32CubeH5 to
build.

YEEP144lib/include/YEEP144_ADCPot.h

@@ -0,0 +1,8 @@
+#ifndef __YEEP144_ADCPOT_H
+#define __YEEP144_ADCPOT_H
+
+void YEEP144_ADCPot_Init(void);
+uint16_t YEEP144_ADCPot_GetPot1(void);
+uint16_t YEEP144_ADCPot_GetPot2(void);
+
+#endif