* configure.in (powerpc-*-aix*): Recognize as a new gdb host

     * configure.in (powerpc-*-aix*): Recognize as a new gdb host
         and target.
         (powerpc-*-eabi*): Don't set configdirs.
         (powerpcle-*-eabi*0: Likewise.
         * configure: Updated.
         * rs6000-nat.c (vmap_ldinfo): Don't relocate data addresses
         for the main objfile if DONT_RELOCATE_SYMFILE_OBJFILE is
         defined.
         * config/powerpc/{aix.mh,aix.mh}: Host and target makefile fragments
         for powerpc running aix4.
         * config/powerpc/{nm-aix.h, tm-ppc-aix.h, xm-aix.h}: Native, target
         and host include files for powerpc running aix4.

More of Mike's powerpc work + minor changes.