net: bridge: vlan: add basic option dumping support

We'll be dumping the options for the whole range if they're equal. The
first range vlan will be used to extract the options. The commit doesn't
change anything yet it just adds the skeleton for the support. The dump
will happen when the first option is added.

Signed-off-by: Nikolay Aleksandrov <nikolay@cumulusnetworks.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

net/bridge/br_vlan_options.c

@@ -0,0 +1,25 @@
+// SPDX-License-Identifier: GPL-2.0-only
+// Copyright (c) 2020, Nikolay Aleksandrov <nikolay@cumulusnetworks.com>
+#include <linux/kernel.h>
+#include <linux/netdevice.h>
+#include <linux/rtnetlink.h>
+#include <linux/slab.h>
+
+#include "br_private.h"
+
+/* check if the options between two vlans are equal */
+bool br_vlan_opts_eq(const struct net_bridge_vlan *v1,
+		     const struct net_bridge_vlan *v2)
+{
+	return true;
+}
+
+bool br_vlan_opts_fill(struct sk_buff *skb, const struct net_bridge_vlan *v)
+{
+	return true;
+}
+
+size_t br_vlan_opts_nl_size(void)
+{
+	return 0;
+}