s390x updates:
- support for vfio-ccw to passthrough channel devices
- allow ccw bios to boot from scsi generic devices
- bugfix for initial reset

# gpg: Signature made Tue 23 May 2017 12:02:24 PM BST
# gpg:                using RSA key 0xDECF6B93C6F02FAF
# gpg: Good signature from "Cornelia Huck <conny@cornelia-huck.de>"
# gpg:                 aka "Cornelia Huck <cohuck@kernel.org>"
# gpg:                 aka "Cornelia Huck <cornelia.huck@de.ibm.com>"
# gpg:                 aka "Cornelia Huck <huckc@linux.vnet.ibm.com>"
# Primary key fingerprint: C3D0 D66D C362 4FF6 A8C0  18CE DECF 6B93 C6F0 2FAF

* cohuck/tags/s390x-20170523: (21 commits)
  s390/kvm: do not reset riccb on initial cpu reset
  MAINTAINERS: Add vfio-ccw maintainer
  vfio/ccw: update sense data if a unit check is pending
  s390x/css: ccw translation infrastructure
  s390x/css: introduce and realize ccw-request callback
  vfio/ccw: get irqs info and set the eventfd fd
  vfio/ccw: get io region info
  vfio/ccw: vfio based subchannel passthrough driver
  s390x/css: device support for s390-ccw passthrough
  s390x/css: realize css_create_sch
  s390x/css: realize css_sch_build_schib
  s390x/css: add s390-squash-mcss machine option
  linux-headers: update
  pc-bios/s390-ccw.img: rebuild image
  pc-bios/s390-ccw: Build a reasonable max_sectors limit
  pc-bios/s390-ccw: Get Block Limits VPD device data
  pc-bios/s390-ccw: Get list of supported VPD pages
  pc-bios/s390-ccw: Refactor scsi_inquiry function
  pc-bios/s390-ccw: Break up virtio-scsi read into multiples
  pc-bios/s390-ccw: Move SCSI block factor to outer read
  ...
Signed-off-by: NStefan Hajnoczi <stefanha@redhat.com>