util-linux: build schedutils without enabling basic binaries

Pull an upstream fix to allow building schedutils (ionice, taskset,
chrt) when util-linux is configured with

  $ configure --disable-all-programs --enable-schedutils

Fixes:
  https://bugs.busybox.net/show_bug.cgi?id=9656



Reported-by: Aaron Holtzman <aholtzma@gmail.com>
Signed-off-by: Carlos Santos <casantos@datacom.ind.br>
Signed-off-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>