Merge remote-tracking branch 'remotes/ehabkost/tags/machine-next-pull-request' into staging

Machine queue, 2019-03-11

* memfd fixes (Ilya Maximets)
* Move nvdimms state into struct MachineState (Eric Auger)
* hostmem-file: reject invalid pmem file sizes (Stefan Hajnoczi)

# gpg: Signature made Tue 12 Mar 2019 00:57:41 GMT
# gpg:                using RSA key 2807936F984DC5A6
# gpg: Good signature from "Eduardo Habkost <ehabkost@redhat.com>" [full]
# Primary key fingerprint: 5A32 2FD5 ABC4 D3DB ACCF  D1AA 2807 936F 984D C5A6

* remotes/ehabkost/tags/machine-next-pull-request:
  memfd: improve error messages
  memfd: set up correct errno if not supported
  memfd: always check for MFD_CLOEXEC
  hostmem-memfd: disable for systems without sealing support
  machine: Move nvdimms state into struct MachineState
  nvdimm: Rename AcpiNVDIMMState into NVDIMMState
  hostmem-file: reject invalid pmem file sizes

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