Fix 3.19-rc6 builds with patch-2.7.3
    
    Upstream patch decided that relative symlinks are dangerous to create via
    patch, so it refuses to do so.  To get the kernel to build, we remove the
    hunk in patch-3.19-rc6.xz that was attempting to create one, and do it
    manually in the spec file.  The spec change should go away when 3.19 final
    is out.