* Idea and part of the patch from HJ.

    * Idea and part of the patch from HJ.
        * Makefile.in: auto-host.h renamed from auto-config.h.  All references
        changed.
        (distclean): Remove auto-build.h too.
        * configure.in: Rename host autoconf generated file to auto-host.h.
        If host != build, then run autoconf to generate auto-build.h for
        the build machine and include it in build_xm_files.
        Check for wait.h and sys/wait.h.

git-svn-id: svn+ssh://gcc.gnu.org/svn/gcc/trunk@19205 138bc75d-0d04-0410-961f-82ee72b054a4