Merge remote-tracking branch 'remotes/cohuck/tags/s390x-20181105' into staging

Merge remote-tracking branch 'remotes/cohuck/tags/s390x-20181105' into staging

- some changes in s390x maintainership
- bugfix in vfio-ap

# gpg: Signature made Mon 05 Nov 2018 16:34:03 GMT
# gpg:                using RSA key DECF6B93C6F02FAF
# gpg: Good signature from "Cornelia Huck <conny@cornelia-huck.de>"
# gpg:                 aka "Cornelia Huck <huckc@linux.vnet.ibm.com>"
# gpg:                 aka "Cornelia Huck <cornelia.huck@de.ibm.com>"
# gpg:                 aka "Cornelia Huck <cohuck@kernel.org>"
# gpg:                 aka "Cornelia Huck <cohuck@redhat.com>"
# Primary key fingerprint: C3D0 D66D C362 4FF6 A8C0  18CE DECF 6B93 C6F0 2FAF

* remotes/cohuck/tags/s390x-20181105:
  MAINTAINERS: s390/boot: the ipl code and the bios belong together
  MAINTAINERS: s390: Remove myself
  MAINTAINERS: s390/pci: add Collin Walling as maintainer for zpci
  MAINTAINERS: s390/virtio-ccw: drop Christian, add Halil
  MAINTAINERS: s390: more maintainers for vfio-ccw
  s390x/vfio-ap: report correct error

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>