gnats bugfix 2699

[drauku <drauku_(_at_)_drauku_(_dot_)_net>]

hello all,
	attached is the patch for user.c in src/usr.sbin/user/

	fixes gnat bug #2699:

	http://cvs.openbsd.org/cgi-bin/wwwgnats.pl/full/2699

thanks,
chris humphries
807a808,810
> 	if (getgrnam(grp->gr_name) == NULL) {
> 		errx(EXIT_FAILURE, "group `%s' does not exist", grp->gr_name); 
> 	}