Fix a significant Win32 problem that the os/win32 path is in all
  the project include lists, and the relative paths fail when ap_config
  and os are both copied to the $(target)/include directory.


git-svn-id: https://svn.apache.org/repos/asf/httpd/httpd/branches/1.3.x@87966 13f79535-47bb-0310-9956-ffa450edef68