[0/5] vmd: generate and expose ACPI tables to the guest via fw_cfg

I tested these changes on a guest running -current, please see below the
relevant diff from dmesg output.

I also tested a recent Linux kernel (6.18.x) and it still boots
successfully.


15,16c15,16
< bios0 at mainbus0: SMBIOS rev. 2.4 @ 0xf2220 (10 entries)
< bios0: vendor SeaBIOS version "1.16.3p1-OpenBSD-vmm" date 01/01/2011
---
> bios0 at mainbus0: SMBIOS rev. 2.4 @ 0xf1d40 (10 entries)
> bios0: vendor SeaBIOS version "1.16.3p2-OpenBSD-vmm" date 01/01/2011
18,19c18,23
< acpi at bios0 not configured
< cpu0 at mainbus0: (uniprocessor)
---
> acpi0 at bios0: ACPI 3.0
> acpi0: sleep states
> acpi0: tables DSDT FACP APIC
> acpi0: wakeup devices
> acpimadt0 at acpi0 addr 0xfee00000: PC-AT compat
> cpu0 at mainbus0: apid 0 (boot processor)
> cpu0: apic clock running at 0MHz