Merge remote-tracking branch 'remotes/cohuck/tags/s390x-20200227' into staging

Includes a headers update against 5.6-current.
- add missing vcpu reset functionality
- rstfy some s390 documentation
- fixes and enhancements

# gpg: Signature made Thu 27 Feb 2020 11:50:08 GMT
# gpg:                using RSA key C3D0D66DC3624FF6A8C018CEDECF6B93C6F02FAF
# gpg:                issuer "cohuck@redhat.com"
# gpg: Good signature from "Cornelia Huck <conny@cornelia-huck.de>" [marginal]
# gpg:                 aka "Cornelia Huck <huckc@linux.vnet.ibm.com>" [full]
# gpg:                 aka "Cornelia Huck <cornelia.huck@de.ibm.com>" [full]
# gpg:                 aka "Cornelia Huck <cohuck@kernel.org>" [marginal]
# gpg:                 aka "Cornelia Huck <cohuck@redhat.com>" [marginal]
# Primary key fingerprint: C3D0 D66D C362 4FF6 A8C0  18CE DECF 6B93 C6F0 2FAF

* remotes/cohuck/tags/s390x-20200227:
  s390x: Rename and use constants for short PSW address and mask
  docs: rstfy vfio-ap documentation
  docs: rstfy s390 dasd ipl documentation
  s390/sclp: improve special wait psw logic
  s390x: Add missing vcpu reset functions
  linux-headers: update
  target/s390x/translate: Fix RNSBG instruction

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

diff --cc MAINTAINERS
Simple merge