Final HS60v2 changes. (#4790)

* initial commit, this now mostly works

- RGB controls work
- Dynamic keymap still broken due to eeprom
- Via works

* STM32 eeprom update

- Update EEPROM emulation library to handle 8bit data like AVR.
- This library also allows for multiple page pairs resulting in greater EEPROM size flexibility

* hs60 changes

* HS60 hhkb added

* Update keyboards/hs60/v2/config.h

Co-Authored-By: yiancar <yiangosyiangou@cytanet.com.cy>

tmk_core/common/chibios/flash_stm32.h

@@ -45,6 +45,7 @@ FLASH_Status FLASH_ProgramHalfWord(uint32_t Address, uint16_t Data);
 
 void FLASH_Unlock(void);
 void FLASH_Lock(void);
+void FLASH_ClearFlag(uint32_t FLASH_FLAG);
 
 #ifdef __cplusplus
 }