[bockbuild] fix wrong setting of GTK2_RC env var
[bockbuild] fix wrong setting of GTK2_RC env var

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