[CentOS-devel] Adding centos-extras to a cbs build target

Hi,
I thought I'd read how to do this somewhere, but I've spent alot of
time searching with no results.

I'm trying to build origin on aarch64, so I am using the
oranges7-test64-common-el7 build target.

The problem is that origin requires golang.  golang for aarch64 is in
centos-extras.  But when I try to build on oranges7, it doesn't see
extras.

What can I do so that oranges sees the centos-extras repo?

Troy
p.s. my build command is
cbs build --scratch --arch-override=aarch64 oranges7-test64-common-el7
origin-1.4.0-1.el7.src.rpm