Now that uname(3) uses sysctl(2), we no longer need sysuname(2).
Backward compatibility is retained for old statically linked
binaries for a short while.
Also remove the now-obsolete MINIX3-specific "arch" field from the
utsname structure. While this is an ABI break at the libc level,
it should pose no problems in practice, because:
- statically linked programs (i.e., all of the base system) are not
affected, as they will use headers synchronized with libc;
- the structure is getting smaller, thus, older dynamically linked
programs (typically in pkgsrc) using the new libc will end up with
garbage in the "arch" field, but it is unlikely they will use this
field anyway, since it was specific to MINIX3;
- new dynamically linked programs using an old libc could end up with
memory corruption, but this is not a scenario that is expected to
occur in the first place - certainly not with programs from pkgsrc.
Change-Id: I29c76576f509feacc8f996f0bd353ca8961d4917
d991a2bea3