kernel/linux: add xz-ed linux tarballs

Signed-off-by: Jerzy Grzegorek <jerzy.grzegorek@trzebnica.net>
Message-Id: <f249828223fc75313bee.1363860871@NX5000>
Patchwork-Id: 229618

 #!/bin/sh

 set -e

 printf "Running autoconf...\n"

 autoconf -Wall --force

 printf "Done. You may now run:\n    ./configure\n"