Enable CONFIG_VFIO_NOIOMMU
This is useful in virtual environments that don't have native iommu support.
It's already enabled in the AMD64 config. And both Ubuntu and Fedora also enable it.
https://git.launchpad.net/~ubuntu-kernel/ubuntu/+source/linux/+git/bionic/tree/debian.master/config/config.common.ubuntu#n9960 https://src.fedoraproject.org/rpms/kernel/blob/rawhide/f/kernel-x86_64-fedora.config#_7567