toolchain/57664: ctf tools don't handle DWARF version 5.

[mrg%eterna.com.au@localhost]

>Number:         57664
>Category:       toolchain
>Synopsis:       ctf tools don't handle DWARF version 5.
>Confidential:   no
>Severity:       serious
>Priority:       high
>Responsible:    toolchain-manager
>State:          open
>Class:          sw-bug
>Submitter-Id:   net
>Arrival-Date:   Tue Oct 17 05:05:00 +0000 2023
>Originator:     matthew green
>Release:        NetBSD 10.99.7
>Organization:
people's front against (bozotic) www (softwar foundation)
>Environment:
all netbsd ports
>Description:
	
	upstream GCC 12 defaults to using DWARF version 5 output,
	which the CTF tools we have in netbsd are unable to handle.

	i changed netbsd native gcc12 to default back to version 4:

	https://mail-index.netbsd.org/source-changes/2023/08/03/msg146601.html

	this is clearly suboptimal and doesn't help eg, GCC 12 in
	pkgsrc, or GCC 13, or beyond etc.

>How-To-Repeat:

	build with -gdwarf-5 and then try to ctfconvert the output.

>Fix: