removing support for old platforms

[Dan Nicolaescu]

RMS has OKed removing support for the platforms in the list below.
(after advertising this on a few relevant list and waiting a few
months).

In order to not leave junk in the tree, we could collect all the symbols
it defines in a new section at the one of admin/CPP-DEFINES. If all the
#defines for a symbol have been removed, then the code that makes
use of that define can be removed.

The MSDOS platform still has some interesting code that we might want to
reuse: it has real menus in text mode, that functionality would be good
to have at some point in the future for terminals.
Eli, how do you wan to handle this?

Help doing this work would be greatly appreciated.

MSDOS
Mac OS all versions before MACOSX (only MAC_OS8 seems to have a special define)

Apollo SR10.x (unexapollo.c)
Convex (unexconvex.c and m/convex.c)
Xenix (unexenix.c and s/xenix.h)
Iris  (unexmips.c m/iris4d.h   m/irist.h    s/iris3-5.h  s/iris3-6.h)
Gould (m/gould*)
Siemens machines running Sinix (unexsni.c)
Harris CXUX (s/cxux*)
ESIX, a variant of v.5.3 for the 386. (s/esix*)
Interactive (ISC) Unix (s/isc*)
Sony News (s/newsos*)
RTU 3.0, ucb universe (s/rtu.h) -- defines NOMULTIPLEJOBS
UniSoft's UniPlus 5.2 (s/uniplus.h)
UMAX (s/umax.h)
AT&T UNIX PC model 7300 (m/7300.h)
Acorn
Alliant (m/alliant*)
Amdahl (m/amdahl*)
Altos 3068 Unix System V Release 2 (m/altos.h)
Apollo (m/apollo.h)
AT&T 3b (m/att3b.h)
Aviion (m/aviion*)
Celerity (m/celerity.h)
clipper (m/clipper.h)
convergent S series (m/cnvrgnt.h)
cydra (m/cydra5.h)
Motorola System V/88 machines (m/delta88k.h) -- gcc dropped support
                              for 88k a while ago
Bull DPX/2 range (m/dpx2.h)
Dual machines using unisoft port (m/dual.h)
Elxsi machine (running enix) (m/elxsi.h)
Fujitsu F301 machine (m/f301.h)
i860 (m/i860.h) gcc dropped support a while ago
ibm ps/2 aix386 (m/ibmps2-aix.h)
ISI 68000's (m/is*)
Masscomp 5000 series running RTU, ucb universe (m/masscomp.h)
Megatest 68000's (m/mega68.h)
Whitechapel Computer Works MG1 (ns16000 based) (m/mg1.h)
Harris Night Hawk Series 1200 and Series 3000 (m/nh3000.h m/nh4000.h)
ns16000 (m/ns16000.h)
National Semiconductor 32000, running Genix (m/ns32000.h)
TI Nu machines using system V (m/nu.h)
HLH Orion (m/orion.h m/orion105.h)
Paragon i860 (m/paragon.h)
PFU A-series (m/pfa50.h)
Plexus running System V.2 (m/plexus.h)
pyramid. (m/pyramid.h)
sh3el (m/sh3el.h)
Bull SPS-7 (m/sps7.h)
m/sr2k.h
Stride (m/stride.h)
Sun 1 (m/sun1.h)
Sun 2 (m/sun2.h)
SEQUENT SYMMETRY  m/symmetry.h
Tadpole 68k machines m/tad68k.h
tahoe m/tahoe.h
targon31 m/targon31.h
Tektronix* (m/tek4300.h m/tekxd88.h)
NCR Tower 32 running System V.2 (m/tower32.h)
NCR Tower 32 running System V.3 (m/tower32v3.h)
U-station (Nihon Unisys, SS5E; Sumitomo Denkoh, U-Station E30). (m/ustation.h)
Wicat (m/wicat.h)
Honeywell XPS100 running UNIX System V.2 (m/xps100.h)


Data General's DG/UX  (s/dgux*)
Irix before version 6
osf1 (s/osf*)
SunOS4 (s/sunos*)
RISCiX (s/riscix*)
SCO 3.2v4 (s/sco4.h)
SCO 3.2v5 (s/sco5.h)
Sun's 386-based RoadRunner (m/sun386.h)
Sun3 machines (m/sun3*)
 Integrated Solutions 386 machine (m/is386.h)