Fix incorrect wording. From Bug Hunting in PR 41989.

share/man/man5/boot.cfg.5

@@ -1,4 +1,4 @@
-.\"	$NetBSD: boot.cfg.5,v 1.15 2008/12/13 23:36:21 christos Exp $
+.\"	$NetBSD: boot.cfg.5,v 1.16 2009/09/04 10:34:16 wiz Exp $
 .\"
 .\" Copyright (c) 2007 Stephen Borrill
 .\" All rights reserved.
@@ -25,7 +25,7 @@
 .\" INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
 .\" THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 .\"
-.Dd December 13, 2008
+.Dd September 4, 2009
 .Dt BOOT.CFG 5
 .Os
 .Sh NAME
@@ -197,7 +197,7 @@ There will be no timeout.
 .Sh HISTORY
 The
 .Nm
-utility appeared in
+file appeared in
 .Nx 5.0 .
 .Sh AUTHORS
 The