mzap_create_impl
mzap_create_impl(mos, object, 0, 0, tx);
void mzap_create_impl(objset_t *os, uint64_t obj, int normflags,
mzap_create_impl(os, obj, normflags, 0, tx);
mzap_create_impl(os, obj, normflags, 0, tx);
mzap_create_impl(os, obj, normflags, flags, tx);