* server/listen.c: detect systemd socket activation using sd_listen_fds(),
drop the support for "Listen systemd" and use standard Listen syntax instead.

This allows using the same configuration file with or without socket activation
and allows setting protocol when using socket activation.



git-svn-id: https://svn.apache.org/repos/asf/httpd/httpd/trunk@1608703 13f79535-47bb-0310-9956-ffa450edef68