$NetBSD: patch-tools_include_Makefile,v 1.1 2020/08/27 08:22:33 bouyer Exp $

--- tools/include/Makefile.orig	2020-08-27 00:04:16.538336097 +0200
+++ tools/include/Makefile	2020-08-27 00:05:22.129359415 +0200
@@ -69,7 +69,7 @@
 	$(INSTALL_DATA) xen/foreign/*.h $(DESTDIR)$(includedir)/xen/foreign
 	$(INSTALL_DATA) xen/hvm/*.h $(DESTDIR)$(includedir)/xen/hvm
 	$(INSTALL_DATA) xen/io/*.h $(DESTDIR)$(includedir)/xen/io
-	$(INSTALL_DATA) xen/sys/*.h $(DESTDIR)$(includedir)/xen/sys
+	$(INSTALL_DATA) xen/sys/*.h $(DESTDIR)$(includedir)/xen/sys || true
 	$(INSTALL_DATA) xen/xsm/*.h $(DESTDIR)$(includedir)/xen/xsm
 
 .PHONY: uninstall