[CentOS] Update from 7.3 to 7.4 failing because of architecture change from PPC64 to PPC

Hello,

I'm having problems updating from 7.3 to 7.4 on my ppc64 (IBM Power7
p770) installation.
yum update stops with
Error:  Multilib version problems found.
[..]
Protected multilib versions: systemd-libs-219-42.el7.ppc !=
systemd-libs-219-42.el7_4.1.ppc64

When I scroll back through the transaction check I see various package
dependencies for *.ppc instead of *.ppc64.
First appearance in the check is glibc.ppc and then everything goes nuts:
[..]
--> Running transaction check
---> Package boost-date-time.ppc64 0:1.53.0-27.el7 will be installed
---> Package elfutils-default-yama-scope.noarch 0:0.168-8.el7 will be installed
---> Package glibc.ppc 0:2.17-196.el7 will be installed
--> Processing Dependency: libfreebl3.so(NSSRAWHASH_3.12.3) for
package: glibc-2.17-196.el7.ppc
--> Processing Dependency: libfreebl3.so for package: glibc-2.17-196.el7.ppc
---> Package grub2-common.noarch 1:2.02-0.64.el7.centos will be installed
---> Package grub2-ppc64.ppc64 1:2.02-0.64.el7.centos will be installed
--> Processing Dependency: grub2-ppc64-modules =
1:2.02-0.64.el7.centos for package:
1:grub2-ppc64-2.02-0.64.el7.centos.ppc64
---> Package gtk-update-icon-cache.ppc64 0:3.22.10-4.el7 will be installed
---> Package libfastjson.ppc64 0:0.99.4-2.el7 will be installed
---> Package libseccomp.ppc64 0:2.3.1-3.el7 will be installed
---> Package nss-pem.ppc64 0:1.0.3-4.el7 will be installed
---> Package python-linux-procfs.noarch 0:0.4.9-3.el7 will be installed
---> Package python-schedutils.ppc64 0:0.4-6.el7 will be installed
---> Package stix-fonts.noarch 0:1.1.0-5.el7 will be installed
---> Package systemd-libs.ppc 0:219-42.el7 will be installed
--> Processing Dependency: libselinux.so.1 for package:
systemd-libs-219-42.el7.ppc
--> Processing Dependency: libpam_misc.so.0(LIBPAM_MISC_1.0) for
package: systemd-libs-219-42.el7.ppc
--> Processing Dependency: libpam_misc.so.0 for package:
systemd-libs-219-42.el7.ppc
--> Processing Dependency: libpam.so.0(LIBPAM_MODUTIL_1.0) for
package: systemd-libs-219-42.el7.ppc
--> Processing Dependency: libpam.so.0(LIBPAM_EXTENSION_1.0) for
package: systemd-libs-219-42.el7.ppc
--> Processing Dependency: libpam.so.0(LIBPAM_1.0) for package:
systemd-libs-219-42.el7.ppc
--> Processing Dependency: libpam.so.0 for package: systemd-libs-219-42.el7.ppc
--> Processing Dependency: liblzma.so.5(XZ_5.0) for package:
systemd-libs-219-42.el7.ppc
--> Processing Dependency: liblzma.so.5 for package: systemd-libs-219-42.el7.ppc
--> Processing Dependency: libgpg-error.so.0 for package:
systemd-libs-219-42.el7.ppc
--> Processing Dependency: libgcrypt.so.11(GCRYPT_1.2) for package:
systemd-libs-219-42.el7.ppc
--> Processing Dependency: libgcrypt.so.11 for package:
systemd-libs-219-42.el7.ppc
--> Processing Dependency: libgcc_s.so.1(GCC_3.3.1) for package:
systemd-libs-219-42.el7.ppc
--> Processing Dependency: libgcc_s.so.1(GCC_3.0) for package:
systemd-libs-219-42.el7.ppc
--> Processing Dependency: libgcc_s.so.1 for package:
systemd-libs-219-42.el7.ppc
--> Processing Dependency: libdw.so.1 for package: systemd-libs-219-42.el7.ppc
--> Processing Dependency: libcap.so.2 for package: systemd-libs-219-42.el7.ppc
--> Running transaction check
---> Package elfutils-libs.ppc 0:0.168-8.el7 will be installed
--> Processing Dependency: elfutils-libelf(ppc-32) = 0.168-8.el7 for
package: elfutils-libs-0.168-8.el7.ppc
--> Processing Dependency: libz.so.1(ZLIB_1.2.2.3) for package:
elfutils-libs-0.168-8.el7.ppc
--> Processing Dependency: libz.so.1 for package: elfutils-libs-0.168-8.el7.ppc
--> Processing Dependency: libelf.so.1(ELFUTILS_1.7) for package:
elfutils-libs-0.168-8.el7.ppc
--> Processing Dependency: libelf.so.1(ELFUTILS_1.6) for package:
elfutils-libs-0.168-8.el7.ppc
--> Processing Dependency: libelf.so.1(ELFUTILS_1.5) for package:
elfutils-libs-0.168-8.el7.ppc
--> Processing Dependency: libelf.so.1(ELFUTILS_1.4) for package:
elfutils-libs-0.168-8.el7.ppc
--> Processing Dependency: libelf.so.1(ELFUTILS_1.3) for package:
elfutils-libs-0.168-8.el7.ppc
--> Processing Dependency: libelf.so.1(ELFUTILS_1.1.1) for package:
elfutils-libs-0.168-8.el7.ppc
--> Processing Dependency: libelf.so.1(ELFUTILS_1.0) for package:
elfutils-libs-0.168-8.el7.ppc
--> Processing Dependency: libelf.so.1 for package:
elfutils-libs-0.168-8.el7.ppc
--> Processing Dependency: libbz2.so.1 for package:
elfutils-libs-0.168-8.el7.ppc
[..]
The current 7.3 has no .ppc at all installed. All filesets are ppc64 or noarch.

Is it possible, that the repo is damaged somehow? How can I create
additional info? Any idea how to fix it?

Regards,
Armin