Reference sha256(1) instead of sha256(8), which doesn't exist.

Index: src/usr.sbin/portsnap/portsnap/portsnap.8
===================================================================
RCS file: /home/ncvs/src/usr.sbin/portsnap/portsnap/portsnap.8,v
retrieving revision 1.6
diff -u -r1.6 portsnap.8
--- src/usr.sbin/portsnap/portsnap/portsnap.8	1 Feb 2006 14:33:14 -0000	1.6
+++ src/usr.sbin/portsnap/portsnap/portsnap.8	26 Feb 2006 15:20:17 -0000
@@ -222,6 +222,6 @@
 .Xr fetch 1
 .Xr fetch 3
 .Xr portsnap.conf 5
-.Xr sha256 8
+.Xr sha256 1
 .Sh AUTHORS
 .An Colin Percival Aq cperciva@FreeBSD.org