Reduce the field widths for the summary line of traps, system calls
and interrupts so that the numbers don't all run into one.
chap-midi is ready for testing.
check if malloc(3) failed

ok joerg@
New stdarg.h and varargs.h based on arm and i386 versions.

Use __builtin_va_* instead of hand written code in va-sh.h that uses
LHS casts.  Slightly worse code is generated by gcc 3.3.3, but LHS
casts are outlawed in gcc 3.3.6 and gcc 4.

Build-tested on hpcsh (le) and mmeye (be), run-tested on hpcsh.
Include <sys/kauth.h> because it's needed.
Nuke va-sh.h.  stdarg.h and varargs.h now use __builtin_va_*.
Remove packed attributes gcc-4 dislikes.
void casts to functions whose return values are ignored.
void casts.
add void casts.
Enable -Wold-style-cast for sh3 now that its stadarg.h doesn't use LHS casts.
add NULLFS and re(4) (both tested.)
apply -Wno-pointer-sign to tp.c.
use "j" instead of "ll" for intmax_t and friends.

XXX: we should probably use "j" for all(?) other platforms as well
(just for intmax_t and friends.)
the intention of the whole tip-as-cu thing was to allow tip-as-cu and
have a cu command installed, even when the rest of uucp was removed
via MKUUCP=no.  The old uucp-derived cu is no more, and is not
installed in either case.

make it so, by correcting some confusion that had made the non-uucp
tip-as-cu cu conditional on MKUUCP
use consistent order of function specifiers and type specifiers.
(int inline -> inline int)
introduce macros, UAREA_TO_USER and USER_TO_UAREA,
to convert uarea VA into a pointer to struct user and vice versa,
so that MD code can change the layout in uarea.
i386 and xen: move struct user to the highest address in uarea
and reduce UPAGES from 4 to 3 in the case of !NOREDZONE.
make sure bswap64() returns an uint64_t, not an unsigned long long,
which is incompatible for gcc4 on alpha at least
sprinkle some __noreturn__ attributes, saves gcc4 warnings elsewhere