Merge remote-tracking branch 'remotes/kraxel/tags/microvm-20200617-pull-request'...

microvm: memory config tweaks

# gpg: Signature made Wed 17 Jun 2020 13:28:44 BST
# gpg:                using RSA key 4CB6D8EED3E87138
# gpg: Good signature from "Gerd Hoffmann (work) <kraxel@redhat.com>" [full]
# gpg:                 aka "Gerd Hoffmann <gerd@kraxel.org>" [full]
# gpg:                 aka "Gerd Hoffmann (private) <kraxel@gmail.com>" [full]
# Primary key fingerprint: A032 8CFF B93A 17A7 9901  FE7D 4CB6 D8EE D3E8 7138

* remotes/kraxel/tags/microvm-20200617-pull-request:
  microvm: move virtio base to 0xfeb00000
  x86: move max-ram-below-4g to pc
  microvm: drop max-ram-below-4g support
  microvm: use 3G split unconditionally

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