Updated makefile to fix the argument mistakes

Makefile

@@ -13,7 +13,7 @@ hash: arozos_file_checksum.sha1
 web: web.tar.gz
 
 clean: 
-	rm -rf arozos_*_*
+	rm -f arozos_*_*
 	rm -f web.tar.gz
 
 $(PLATFORMS):