more cleanup for DSN drafts

more cleanup for DSN drafts

SCCS-vsn: usr.sbin/sendmail/src/usersmtp.c 8.41
SCCS-vsn: usr.sbin/sendmail/src/recipient.c 8.75
SCCS-vsn: usr.sbin/sendmail/src/main.c 8.93
SCCS-vsn: usr.sbin/sendmail/src/envelope.c 8.56
SCCS-vsn: usr.sbin/sendmail/src/parseaddr.c 8.61
SCCS-vsn: usr.sbin/sendmail/src/sendmail.h 8.107
SCCS-vsn: usr.sbin/sendmail/src/savemail.c 8.60
SCCS-vsn: usr.sbin/sendmail/src/srvrsmtp.c 8.62
SCCS-vsn: usr.sbin/sendmail/src/deliver.c 8.137
SCCS-vsn: usr.sbin/sendmail/src/queue.c 8.74
SCCS-vsn: usr.sbin/sendmail/src/alias.c 8.40
SCCS-vsn: usr.sbin/sendmail/src/udb.c 8.16