[bockbuild] add default GnuXzPackage
[bockbuild] add default GnuXzPackage

mono/bockbuild,bl8/bockbuild,BansheeMediaPlayer/bockbuild,BansheeMediaPlayer/bockbuild,mono/bockbuild,bl8/bockbuild,bl8/bockbuild,BansheeMediaPlayer/bockbuild