bin/55962: Some tar(1) error messages lack file name and newline

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

>Number:         55962
>Category:       bin
>Synopsis:       Some tar(1) error messages lack file name and newline
>Confidential:   no
>Severity:       serious
>Priority:       medium
>Responsible:    bin-bug-people
>State:          open
>Class:          sw-bug
>Submitter-Id:   net
>Arrival-Date:   Thu Jan 28 18:20:00 +0000 2021
>Originator:     Andreas Gustafsson
>Release:        NetBSD-current, source date 2021.01.28.11.45.31
>Organization:
>Environment:
System: NetBSD
Architecture: x86_64
Machine: amd64
>Description:

I am getting error messages like these from the -current tar(1):

  : tar format cannot archive socket: tar format cannot archive socket: tar format cannot archive socket: tar format cannot archive socket: tar format cannot archive socket: tar format cannot archive socket

That is, the messages are missing a terminating newline, as well as
whatever is supposed to go before the initial colon, presumably the
name of the file that could not be archived.

>How-To-Repeat:

>Fix: