For now, we enumerate disk devices before network devices. This is to
work around an interaction between u-boot and bhyve's BAR registration
code, reported here: https://lists.freebsd.org/archives/freebsd-virtualization/2024-April/002103.html
The console and bootrom are specified slightly differently versus amd64,
and a few of vmrun.sh's command-line options are amd64-only.