x64.conf: add virtio modules as MACHINE_ESSENTIAL
x64.conf: add virtio modules as MACHINE_ESSENTIAL

Allow virtio block devices, serial consoles, and network devices to be
usable in the minimal images. Also enable memory balloon support to
potentially improve memory utilization in overcommitted hypervisors.

Signed-off-by: Richard Tollerton <67c688e7f7482ba5c4ebe3d70bc77594748182a6@ni.com>
Natinst-Reviewboard-ID: 109785

ni/meta-nilrt,ni/meta-nilrt,ni/meta-nilrt,ni/meta-nilrt,ni/meta-nilrt