Merge remote-tracking branch 'cohuck/tags/s390x-20170502' into staging

More s390x patches, this time boot related:
- LOADPARM machine property, exposed to the guest via SCLP and
  diagnose 308
- Use LOADPARM in the s390-ccw bios to select a boot entry
- Fix a crash in the ipl device code when a virtio-scsi-pci device
  has been specified

# gpg: Signature made Tue 02 May 2017 02:29:26 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-20170502:
  hw/s390x/ipl: Fix crash with virtio-scsi-pci device
  pc-bios/s390-ccw.img: update image
  pc-bios/s390-ccw: add boot entry selection to El Torito routine
  pc-bios/s390-ccw: add boot entry selection for ECKD DASD
  pc-bios/s390-ccw: provide entry selection on LOADPARM for SCSI disk
  pc-bios/s390-ccw: provide a function to interpret LOADPARM value
  pc-bios/s390-ccw: get LOADPARM stored in SCP Read Info
  pc-bios/s390-ccw: Make ebcdic/ascii conversion public
  util/qemu-config: Add loadparm to qemu machine_opts
  hw/s390x/sclp: update LOADPARM in SCP Info
  hw/s390x/ipl: enable LOADPARM in IPIB for a boot device
  hw/s390x: provide loadparm property for the machine

Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>