port-arm/58100: /dev/ttyVI* (viocon(4), virtio-serial) is missing on aarch64

[campbell+netbsd%mumble.net@localhost]

>Number:         58100
>Category:       port-arm
>Synopsis:       /dev/ttyVI* (viocon(4), virtio-serial) is missing on aarch64
>Confidential:   no
>Severity:       serious
>Priority:       medium
>Responsible:    port-arm-maintainer
>State:          open
>Class:          sw-bug
>Submitter-Id:   net
>Arrival-Date:   Tue Apr 02 04:10:00 +0000 2024
>Originator:     Taylor R Campbell
>Release:        current, 10
>Organization:
The NettyBSD Foundation
>Environment:
>Description:
When I imported viocon(4) I tested it on aarch64, and added it to etc/etc.${MACHINE}/MAKEDEV.conf for each MACHINE that seemed appropriate:

https://mail-index.netbsd.org/source-changes/2022/08/12/msg140229.html

But somehow I missed aarch64's MAKEDEV.conf -- possibly because of this somewhat baffling special case in etc/Makefile:

    188 MAKEDEV_MACHINE=${"${MACHINE_CPU}" == "aarch64":?${MACHINE_CPU}:${MACHINE}}
    189 MAKEDEV: ${.CURDIR}/MAKEDEV.awk ${.CURDIR}/MAKEDEV.tmpl \
    190     ${.CURDIR}/etc.${MAKEDEV_MACHINE}/MAKEDEV.conf
    191 	${_MKTARGET_CREATE}
    192 	MACHINE=${MAKEDEV_MACHINE:Q} MACHINE_ARCH=${MACHINE_ARCH:Q} \
    193 	    NETBSDSRCDIR=${NETBSDSRCDIR:Q} \
    194 	    ${TOOL_AWK} -f ${.CURDIR}/MAKEDEV.awk ${.CURDIR}/MAKEDEV.tmpl \
    195 	    > ${.TARGET}

https://nxr.netbsd.org/xref/src/etc/Makefile?r=1.469#188
>How-To-Repeat:
try to use virtio-serial on aarch64
>Fix:
Add `makedev ttyVI' to etc.aarch64/MAKEDEV.conf.