Correctly compare EdiPartyName in GENERAL_NAME_cmp()

If a GENERAL_NAME field contained EdiPartyName data then it was
incorrectly being handled as type "other". This could lead to a
segmentation fault.

Many thanks to David Benjamin from Google for reporting this issue.

CVE-2020-1971

Reviewed-by: Tomas Mraz <tmraz@fedoraproject.org>
