Remove some macros that are either not used anymore or don't really

need documenting here.

admin/CPP-DEFINES

@@ -53,8 +53,6 @@ CLASH_DETECTION
 COFF
 FIRST_PTY_LETTER
 HAVE_PTYS
-HAVE_TERMIO
-HAVE_TERMIOS
 INTERRUPT_INPUT
 NARROWPROTO
 SEPCHAR
@@ -175,7 +173,6 @@ HAVE_SYS_SYSTEMINFO_H
 HAVE_SYS_TIMEB_H
 HAVE_SYS_TIME_H
 HAVE_TCATTR
-HAVE_TERMIOS_H
 HAVE_TIMEVAL
 HAVE_TM_ZONE
 HAVE_TZSET
@@ -258,14 +255,9 @@ USG5_4
 USG_SUBTTY_WORKS
 VALBITS
 WRETCODE
-XINT
 XOS_NEEDS_TIME_H
-XPNTR
-XSET
-XUINT
 _AIX
 _ARCH_PPC64
-_CALLBACK_
 _FILE_OFFSET_BITS
 _LP64
 _MALLOC_INTERNAL
@@ -273,21 +265,6 @@ _NAIVE_DOS_REGS
 _VARARGS_
 _WINSOCKAPI_
 _WINSOCK_H
-__ELF__
-__FreeBSD__
-__GNUC__
-__GNU_LIBRARY__
-__GNUC_MINOR__
-__NetBSD__
-__OpenBSD__
-__STDC__
-__arch64__
-__cplusplus
-__hpux
-__ia64__
-__linux__
-__mc68000__
-__mips__
 _longjmp
 _setjmp
 _start
@@ -323,9 +300,7 @@ getenv
 getpid
 getuid
 gmtime
-i386
 index
-init_process
 isatty
 kill
 link
@@ -333,7 +308,6 @@ linux
 localtime
 logb
 lseek
-m68k
 malloc
 mkdir
 mktemp