Comment # 6 on bug 919420 from Martin Pluskal

(In reply to Charles Arnold from comment #5)
> I haven't worked on a ppc64le machine before so this is just a guess
> but have you tried passing '--os-variant sles12' to see if that
> makes a difference?

Unfortunately it does not help:
[root@ps64vt1060 ~]# virt-install --location
http://download.suse.de/install/SLP/SLE-12-Server-GM/ppc64le/DVD1/ --name
sles12-install --memory 1024 --disk size=10 --graphics vnc  --os-variant sles12
ERROR    Distro 'sles12' does not exist in our dictionary

So only viable installation now is to use bundled kimchi.