mpm_default.h is just a convenience for a specific MPM with 2.3+;

it isn't installed

(this is the only definition at present for DEFAULT_REL_RUNTIMEDIR
on Windows, but that needs to be solved separately)


git-svn-id: https://svn.apache.org/repos/asf/httpd/httpd/trunk@1085947 13f79535-47bb-0310-9956-ffa450edef68