scripts/functions: add xz-ed linux tarballs

Signed-off-by: Jerzy Grzegorek <jerzy.grzegorek@trzebnica.net>
Message-Id: <d0ec17a687dc80754e0f.1363860872@NX5000>
Patchwork-Id: 229619

 # windows config options

 ## depends on ARCH_x86

 ##

 ## select WINDOWS

 ##

 ## help Build a toolchain targeting systems running Windows as host