port-sparc/59203: fs/tmpfs/t_vnd:basic test case fails on sparc and sparc64

[gson%gson.org@localhost (Andreas Gustafsson)]

>Number:         59203
>Category:       port-sparc
>Synopsis:       fs/tmpfs/t_vnd:basic test case fails on sparc and sparc64
>Confidential:   no
>Severity:       non-critical
>Priority:       medium
>Responsible:    port-sparc-maintainer
>State:          open
>Class:          sw-bug
>Submitter-Id:   net
>Arrival-Date:   Fri Mar 21 13:35:00 +0000 2025
>Originator:     Andreas Gustafsson
>Release:        NetBSD-current, source date >= 2024.04.04.16.57.45
>Organization:
  
>Environment:
System: NetBSD
Architecture: sparc
Machine: sparc
>Description:

The fs/tmpfs/t_vnd:basic test case is failing on the sparc and sparc64 testbeds
since the commit of src/tests/fs/tmpfs/t_vnd.sh 1.13 on 2024.04.04.16.57.45.
It passes on other ports.

Logs:

  https://releng.netbsd.org/b5reports/sparc/commits-2024.04.html#2024.04.04.16.57.45
  https://releng.netbsd.org/b5reports/sparc64/commits-2024.04.html#2024.04.04.16.57.45
  https://www.netbsd.org/~martin/sparc64-atf/960_atf.html#fs_tmpfs_t_vnd_basic

>How-To-Repeat:

Run the ATF tests on sparc or sparc64, in qemu or on real hardware.

>Fix: