Powerpc in the build farm

[Andreas Enge]

Hello,

when looking at the powerpc machines at
   https://ci.guix.gnu.org/workers
one sees that only one slot out of two is used on guixp9, and nothing
at all on sjd-p9.

Could someone with knowledge how cuirass is set up on berlin have a look,
please? In the meantime, I will just connect manually to sjd-p9 and try
to compute a few packages, in the hope they will be picked up later.

Andreas