* hppa.c: Conditionalize on HOST_HPPAHPUX instead of hp9000s800.

* hppa.c:  Conditionalize on HOST_HPPAHPUX instead of hp9000s800.
Get rid of HPPA/BSD specific code.  That will go somewhere else
someday.
* (fill_spaces):  Don't spin forever and die if you don't find
$MILLICODE$ subspace.
* (hppa_object_p):  Make sure that we have a real honest-to-cthulu
exec file!
* (hppa_core_file_failing_signal, hppa_core_file_failing_command):
Make these work for HPUX.
* (make_bfd_asection):  New routine to make section creation a
little easier.
* (hppa_core_file_p):  Completely rewrite, leave out bugs.
* libhppa.h:  #include the right system files.  Redefine all of
the structs/macros for hacking core files to use more sensible
HPUX core file structures.
* targets.c (target_vector):  Conditionalize hppa_vec on
HOST_HPPAHPUX, not hp9000s800.
* hosts/hppahpux.h:  #include stdlib.h to get correct decls for
malloc and realloc.  #define HOST_HPPAHPUX.