kcf_walk_ntfylist
kcf_walk_ntfylist(CRYPTO_EVENT_MECHS_CHANGED, &ec);
kcf_walk_ntfylist(CRYPTO_EVENT_MECHS_CHANGED, &ec);
kcf_walk_ntfylist(is_added ? CRYPTO_EVENT_PROVIDER_REGISTERED :
extern void kcf_walk_ntfylist(uint32_t, void *);