Downstream bug: https://bugzilla.redhat.com/show_bug.cgi?id=926780 Please update autoconf to at least 2.69 so aarch64 compiles can happen. Thanks.
This was left at 2.60 to be consistent with the rest of 4.12. You can run xdt-autogen probably if needed, but you should probably be using xfce4-pulseaudio-plugin at this point anyway.