int fw_cfg_add_i64(FWCfgState *s, uint16_t key, uint64_t value);
int fw_cfg_add_callback(FWCfgState *s, uint16_t key, FWCfgCallback callback,
void *callback_opaque, uint8_t *data, size_t len);
int fw_cfg_add_i64(FWCfgState *s, uint16_t key, uint64_t value);
int fw_cfg_add_callback(FWCfgState *s, uint16_t key, FWCfgCallback callback,
void *callback_opaque, uint8_t *data, size_t len);