add option for cleaning all ipkg info before the image build

SVN-Revision: 9151

package/Makefile

@@ -35,6 +35,7 @@ $(curdir)/rootfs-prepare: $(TMP_DIR)/.build
 	@-find $(TARGET_DIR) -name CVS   | $(XARGS) rm -rf
 	@-find $(TARGET_DIR) -name .svn  | $(XARGS) rm -rf
 	@-find $(TARGET_DIR) -name '.#*' | $(XARGS) rm -f
+	$(if $(CONFIG_CLEAN_IPKG),rm -rf $(TARGET_DIR)/usr/lib/ipkg)
 
 $(curdir)/index: FORCE
 	@(cd $(PACKAGE_DIR); $(SCRIPT_DIR)/ipkg-make-index.sh . > Packages)