The NO_ASN1_OLD define was introduced in 0.9.7, 8 years ago, to allow for
obsolete (and mostly internal) routines to be compiled out.
We don't expect any reasonable software to stick to these interfaces, so better
clean up the view and unifdef -DNO_ASN1_OLD.
The astute reader will notice the existence of NO_OLD_ASN1 which serves a
similar purpose, but is more entangled. Its time will come, soon.