Replace some .Xr to non-existing man pages with .Ic (since we don't

even have the matching programs).

usr.bin/error/error.1

@@ -1,4 +1,4 @@
-.\"	$NetBSD: error.1,v 1.6 1999/03/22 18:16:36 garbled Exp $
+.\"	$NetBSD: error.1,v 1.7 2001/05/08 17:18:04 wiz Exp $
 .\"
 .\" Copyright (c) 1980, 1990, 1993
 .\"	The Regents of the University of California.  All rights reserved.
@@ -147,12 +147,12 @@ knows about the error messages produced by:
 .Xr make 1 ,
 .Xr \&cc 1 ,
 .Xr cpp 1 ,
-.Xr ccom 1 ,
+.Ic ccom ,
 .Xr \&as 1 ,
 .Xr \&ld 1 ,
 .Xr lint 1 ,
-.Xr \&pi 1 ,
-.Xr \&pc 1 ,
+.Ic \&pi ,
+.Ic \&pc ,
 .Xr f77 1 ,
 and
 .Em DEC Western Research Modula\-2 .