port-arm/57111: pinebook:sudden reboot when output audio interface

[jun%soum.co.jp@localhost]

>Number:         57111
>Category:       port-arm
>Synopsis:       pinebook:sudden reboot when output audio interface
>Confidential:   no
>Severity:       serious
>Priority:       medium
>Responsible:    port-arm-maintainer
>State:          open
>Class:          sw-bug
>Submitter-Id:   net
>Arrival-Date:   Thu Dec 15 03:55:01 +0000 2022
>Originator:     Jun Ebihara
>Release:        NetBSD 9.99.108 (GENERIC64) #0: Mon Dec 12 21:14:15 UTC 2022
>Organization:
SOUM Corporation
>Environment:
NetBSD pinebook.soum.co.jp 9.99.108 NetBSD 9.99.108 (GENERIC64) #0: Mon Dec 12 21:14:15 UTC 2022  mkrepro%mkrepro.NetBSD.org@localhost:/usr/src/sys/arch/evbarm/compile/GENERIC64 evbarm
>Description:
On pinebook, system reboot, when output audio device.

% cat a.wav > /dev/audio

system rebooting.

related PR: #57030
http://gnats.netbsd.org/cgi-bin/query-pr-single.pl?number=57030

>How-To-Repeat:
1. boot pinebook with NetBSD-current GENERIC64.202210300100UTC later.
2. check aiomixer can manipulate audio device. 

% aiomixer

3. output to audio device

cat a.wav > /dev/audio

system reboot with no message.
>Fix: