K 10
svn:author
V 6
emaste
K 8
svn:date
V 27
2022-02-05T16:28:30.450912Z
K 7
svn:log
V 504
dma: limit lines to 998 characters

Per RFC2822 the maximum transmitted line length is "998 characters...
excluding the CRLF."  In a file the maximum is 999 with the \n included.

Previously mail containing a line with exactly 999 characters would
bounce.

PR:		208261
Reported by:	Helge Oldach
MFC after:	1 week
Sponsored by:	The FreeBSD Foundation

(cherry picked from commit 1a0dde338df8b493d74dcb2f7bbaaa6c02cab371)

Git Hash:   5c1ee92b0ebab49577d065baf7f37a8ffcde4259
Git Author: emaste@FreeBSD.org
END