Use parse_rtattr_nested

(Logical change 1.129)
diff --git a/tc/m_mirred.c b/tc/m_mirred.c
index 585f674..3661297 100644
--- a/tc/m_mirred.c
+++ b/tc/m_mirred.c
@@ -263,8 +263,7 @@
 	if (arg == NULL)
 		return -1;
 
-	memset(tb, 0, sizeof (tb));
-	parse_rtattr(tb, TCA_MIRRED_MAX, RTA_DATA(arg), RTA_PAYLOAD(arg));
+	parse_rtattr_nested(tb, TCA_MIRRED_MAX, arg);
 
 	if (tb[TCA_MIRRED_PARMS] == NULL) {
 		fprintf(f, "[NULL mirred parameters]");