* configure.in, acinclude.m4: Move systemd check to APACHE_CHECK_SYSTEMD
  and use pkg-config where available.


git-svn-id: https://svn.apache.org/repos/asf/httpd/httpd/trunk@1614821 13f79535-47bb-0310-9956-ffa450edef68
* acinclude.m4 (APACHE_CHECK_SYSTEMD): Check first for libsystemd
  with pkg-config since libsystemd-daemon is deprecated upstream.


git-svn-id: https://svn.apache.org/repos/asf/httpd/httpd/trunk@1614823 13f79535-47bb-0310-9956-ffa450edef68
* acinclude.m4 (APACHE_CHECK_SYSTEMD): Actually use $PKGCONFIG, duh.


git-svn-id: https://svn.apache.org/repos/asf/httpd/httpd/trunk@1614824 13f79535-47bb-0310-9956-ffa450edef68