Fix a build error on i386 by casting a ptrdiff_t expression to u_int

(which is safe in this context).  The same build error does not appear
on amd64.  I don't understand this.
ok giovanni@

comms/hylafax/patches/patch-faxd_faxQueueApp_c++

@@ -0,0 +1,12 @@
+$OpenBSD: patch-faxd_faxQueueApp_c++,v 1.1 2010/07/13 15:19:10 naddy Exp $
+--- faxd/faxQueueApp.c++.orig	Sun Jul 11 21:31:17 2010
++++ faxd/faxQueueApp.c++	Sun Jul 11 21:31:42 2010
+@@ -1022,7 +1022,7 @@ faxQueueApp::preparePageChop(const FaxRequest& req,
+ 	if (dec.getLastBlanks() > minRows)
+ 	{
+ 	    pagehandling.append(fxStr::format("Z%04x",
+-		fxmin((unsigned)0xFFFF, stripSize - (dec.getEndOfPage() - data))));
++		fxmin((unsigned)0xFFFF, stripSize - (u_int)(dec.getEndOfPage() - data))));
+ 	}
+     }
+     delete [] data;