Backport:

Backport:

*) mod_http2: when a server is restarted gracefully, any idle h2 worker
   threads are shut down immediately.
   Also, change OpenSSL API use for deprecations in OpenSSL 3.0.
   Adds all other, never proposed code changes to make a clean
   sync of http2 sources.
   trunk patch: http://svn.apache.org/r1893214
                http://svn.apache.org/r1893215
                http://svn.apache.org/r1893220
                and other never proposed code changes
   PR: https://github.com/apache/httpd/pull/270
   +1: icing, rpluem, minfrin

git-svn-id: https://svn.apache.org/repos/asf/httpd/httpd/branches/2.4.x@1893658 13f79535-47bb-0310-9956-ffa450edef68