Merge remote-tracking branch 'remotes/cohuck/tags/s390x-20180409' into staging

Fixes for s390x: kvm, vfio-ccw, ipl code, bios. Includes a rebuild
of s390-ccw.img and s390-netboot.img.

# gpg: Signature made Mon 09 Apr 2018 16:08:19 BST
# gpg:                using RSA key DECF6B93C6F02FAF
# gpg: Good signature from "Cornelia Huck <[email protected]>"
# gpg:                 aka "Cornelia Huck <[email protected]>"
# gpg:                 aka "Cornelia Huck <[email protected]>"
# gpg:                 aka "Cornelia Huck <[email protected]>"
# gpg:                 aka "Cornelia Huck <[email protected]>"
# Primary key fingerprint: C3D0 D66D C362 4FF6 A8C0  18CE DECF 6B93 C6F0 2FAF

* remotes/cohuck/tags/s390x-20180409:
  s390x: load_psw() should only exchange the PSW for KVM
  s390x/mmu: don't overwrite pending exception in mmu translate
  vfio-ccw: fix memory leaks in vfio_ccw_realize()
  pc-bios/s390: update images
  s390: Do not pass inofficial IPL type to the guest
  s390: Ensure IPL from SCSI works as expected
  s390: Refactor IPL parameter block generation
  s390x/kvm: call cpu_synchronize_state() on every kvm_arch_handle_exit()

Signed-off-by: Peter Maydell <[email protected]>