Add support for extracting the msUPN and dnsSRV forms
of subjectAltName entries of type "otherName" into
SSL_{CLIENT,SERVER}_SAN_OTHER_{msUPN,dnsSRV}_n environment
variables. Addresses PR 58020.

* docs/manual/mod/mod_ssl.xml: add SSL_*_SAN_OTHER_*_n entries to the
  environment variables table

* modules/ssl/ssl_engine_vars.c: add support for retrieving the
  SSL_{CLIENT,SERVER}_SAN_OTHER_{msUPN,dnsSRV}_n variables

* modules/ssl/ssl_util_ssl.c: add parse_otherName_value, which
  currently recognizes the "msUPN" (1.3.6.1.4.1.311.20.2.3) and
  "id-on-dnsSRV" (1.3.6.1.5.5.7.8.7) otherName forms, and
  adapt modssl_X509_getSAN to take an optional otherName form
  argument for the GEN_OTHERNAME case

* modules/ssl/ssl_util_ssl.h: adapt modssl_X509_getSAN prototype

* modules/ssl/mod_ssl.c: register the id-on-dnsSRV otherName form
  OID (1.3.6.1.5.5.7.8.7) in OpenSSL's objects table

Proposed by: kbrand
Reviewed by: ylavic, jorton


git-svn-id: https://svn.apache.org/repos/asf/httpd/httpd/branches/2.4.x@1706006 13f79535-47bb-0310-9956-ffa450edef68