Merge remote-tracking branch 'remotes/borntraeger/tags/s390x-20170608' into staging

Merge remote-tracking branch 'remotes/borntraeger/tags/s390x-20170608' into staging

s390x: misc fixes

bunch of fixes
- reject MIDA accesses for CCWs
- cpumodel fixes
- cross-build fix for bios
- migration improvements

# gpg: Signature made Thu 08 Jun 2017 14:10:29 BST
# gpg:                using RSA key 0x117BBC80B5A61C7C
# gpg: Good signature from "Christian Borntraeger (IBM) <borntraeger@de.ibm.com>"
# Primary key fingerprint: F922 9381 A334 08F9 DBAB  FBCA 117B BC80 B5A6 1C7C

* remotes/borntraeger/tags/s390x-20170608:
  s390x/cpumodel: improve defintion search without an IBC
  s390x/cpumodel: take care of the cpuid format bit for KVM
  pc-bios/s390-ccw: use STRIP variable in Makefile
  s390x/css: fence off MIDA
  s390x/css: catch section mismatch on load

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