pack_cis: Clean generated parser sources
diff --git a/Makefile b/Makefile
index 6a1ba4e..d2868ec 100644
--- a/Makefile
+++ b/Makefile
@@ -25,7 +25,7 @@
 
 clean:
 	rm -f core core.* *.o *.s *.a *~ .depend .depfiles/*.d
-	rm -f $(TOOLS)
+	rm -f $(TOOLS) lex_cis.c yacc_cis.c yacc_cis.h
 
 install: $(TOOLS)
 	@mkdir -p $(PREFIX)/sbin