Merge r330246, r330257 from trunk:

* build/config_vars.sh.in: Prepend DESTDIR to paths to installed
apr/apu-config scripts.

* build/config_vars.sh.in: Check for the *-config scripts both at the
DESTDIR-relocated path and at the not-relocated path, to cope with
both builds with and without the bundled APR.

Submitted by: Torsten Foertsch <torsten.foertsch gmx.net>, jorton


git-svn-id: https://svn.apache.org/repos/asf/httpd/httpd/branches/2.2.x@331604 13f79535-47bb-0310-9956-ffa450edef68