rev-list: fix finish_object() call

The callback to traverse_commit_list() are to take linked name_path and
a string for the last path component.

If the callee used its parameters, it would have seen duplicated leading
paths. In this particular case, the callee does not use this argument but
that is not a reason to leave the call broken.

Signed-off-by: Junio C Hamano <gitster@pobox.com>

builtin/rev-list.c

@@ -182,7 +182,7 @@ static void show_object(struct object *obj, const struct name_path *path, const
 	 */
 	const char *ep = strchr(name, '\n');
 
-	finish_object(obj, path, name);
+	finish_object(obj, path, component);
 	if (ep) {
 		printf("%s %.*s\n", sha1_to_hex(obj->sha1),
 		       (int) (ep - name),