* Makefile.in (install-build, install-headers, install-conf): Minor

cleanup: use MKINSTALLDIRS unconditionally since mkdir.sh already
checks whether the target exists; use INSTALL_DATA throughout.  Stop
trying to install os/*/os-inline.c which don't exist any more.


git-svn-id: https://svn.apache.org/repos/asf/httpd/httpd/trunk@189585 13f79535-47bb-0310-9956-ffa450edef68