port GDB to ia64-hpux (native).

port GDB to ia64-hpux (native).

ChangeLog:

        * configure.ac: Remove readline, mmalloc, and gdb from noconfigdirs
        for ia64-hpux.
        * configure: Regenerate.

gdb/ChangeLog:

        * config/ia64/hpux.mh, ia64-hpux-nat.c, ia64-hpux-tdep.c,
        ia64-hpux-tdep.h, solib-ia64-hpux.c, solib-ia64-hpux.h: New files.

        * configure.host: Add handling for ia64-hpux hosts.  Add associated
        floatformats.
        * configure.tgt: Add handling for ia64-hpux targets.
        * Makefile.in (ALL_64_TARGET_OBS): Add ia64-hpux-tdep.o.
        (HFILES_NO_SRCDIR): Add ia64-hpux-tdep.h.
        (ALLDEPFILES): Add ia64-hpux-nat.c ia64-hpux-tdep.c.