Improve code and add a Flash CRC check

stm-firmware/include/reflow-controller/safety/safety-controller.h

@@ -267,6 +267,13 @@ int safety_controller_set_overtemp_limit(float over_temperature);
  */
 float safety_controller_get_overtemp_limit(void);
 
+/**
+ * @brief Perform a CRC check of the flash memory and set appropriate flags
+ * @return negative if internal error occured. Otherwise (independent from CRC check result) 0.
+ * @note This function requires the safety controller to be set up before!
+ */
+int safety_controller_trigger_flash_crc_check(void);
+
 #endif /* __SAFETY_CONTROLLER_H__ */
 
 /** @} */