* config.guess: Add support for i386-pc-interix.

        * config.sub: Likewise.
        * configure.in: Likewise.
        * config/mh-interix: New file.


git-svn-id: svn+ssh://gcc.gnu.org/svn/gcc/trunk@24913 138bc75d-0d04-0410-961f-82ee72b054a4