The patch below does some minor cleanup of adventure(6): an additional

The patch below does some minor cleanup of adventure(6): an additional
use of const I missed in bin/6041; avoiding a signed/unsigned warning;
marking an unused parameter as such; revoking setgid privileges
(including the saved gid) rather than setuid ones; includes and
function prototypes in setup.c; the string passed to err() should not
end with a `.'.  Together with the patch sent concerning adventure's
EOF handling, this synchronises adventure(6) in NetBSD with the Linux
port of the NetBSD games.

Via PR 6557 by Joseph Myers <jsm28@cam.ac.uk>