bin/57978: ifconfig(8) doesn't display inet6 pltime or vltime

[campbell+netbsd%mumble.net@localhost]

>Number:         57978
>Category:       bin
>Synopsis:       ifconfig(8) doesn't display inet6 pltime or vltime
>Confidential:   no
>Severity:       serious
>Priority:       medium
>Responsible:    bin-bug-people
>State:          open
>Class:          sw-bug
>Submitter-Id:   net
>Arrival-Date:   Sat Mar 02 00:50:00 +0000 2024
>Originator:     Taylor R Campbell
>Release:        current, 10, 9, 8
>Organization:
The NetBSDv6 Foundation
>Environment:
>Description:
ifconfig(8) doesn't display the preferred or valid lifetimes of inet6 addresses.
>How-To-Repeat:
ifconfig -a
>Fix:
Yes, please!

Cursory glance at FreeBSD and OpenBSD suggest they will display the pltime and vltime of each inet6 address on the same line as the address and scope id, as ` pltime <duration> vltime <duration>', with <duration> being a decimal integer number of seconds or the text `infty'.