tools/Rules.mk: fix distclean

Running 'make distclean' under tools will currently result in:

tools/Rules.mk:245: *** You have to run ./configure before building or installing the tools.  Stop.

This patch adds 'distclean', 'subdir-distclean%' and 'subdir-clean%' to
no-configure-targets, which allows 'make distclean' to run to completion.

Fixes: 00691c6c (tools: Allow to make *-dir-force-update without ./configure)
Signed-off-by: Paul Durrant <pdurrant@amazon.com>
Acked-by: Ian Jackson <ian.jackson@eu.citrix.com>
Acked-by: Wei Liu <wl@xen.org>

tools/Rules.mk

@@ -239,7 +239,7 @@ subdir-all-% subdir-clean-% subdir-install-% subdir-uninstall-%: .phony
 subdir-distclean-%: .phony
 	$(MAKE) -C $* distclean
 
-no-configure-targets := clean subtree-force-update-all %-dir-force-update
+no-configure-targets := distclean subdir-distclean% clean subdir-clean% subtree-force-update-all %-dir-force-update
 ifeq (,$(filter $(no-configure-targets),$(MAKECMDGOALS)))
 $(XEN_ROOT)/config/Tools.mk:
 	$(error You have to run ./configure before building or installing the tools)