Add support for unusal 'othername' subjectAltNames

Add support for unusal 'othername' subjectAltNames

Increasingly certificates seem to have special things in the subjectAltName that have arbitrary strings in them.

E.g. some (now) common in EU export certificates and, for a few years now, certificates issued to medical doctors (in for example the netherlands, the full spec is https://www.uziregister.nl/Media/Default/PDF/20200325%20CA%20model%20pasmodel%20certificaatprofielen%20v10_0.pdf, section 4.8, page 16 for an example of one country).

Reviewed-by: Tomas Mraz <tmraz@fedoraproject.org>
Reviewed-by: Dmitry Belyavskiy <beldmit@gmail.com>
(Merged from https://github.com/openssl/openssl/pull/11599)