net: openvswitch: remove unused keep_flows

keep_flows was introduced by [1], which used as flag to delete flows or not.
When rehashing or expanding the table instance, we will not flush the flows.
Now don't use it anymore, remove it.

[1] - https://github.com/openvswitch/ovs/commit/acd051f1761569205827dc9b037e15568a8d59f8
Cc: Pravin B Shelar <pshelar@ovn.org>
Signed-off-by: Tonghao Zhang <xiangxia.m.yue@gmail.com>
Acked-by: Pravin B Shelar <pshelar@ovn.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

net/openvswitch/flow_table.c

@@ -168,7 +168,6 @@ static struct table_instance *table_instance_alloc(int new_size)
 
 	ti->n_buckets = new_size;
 	ti->node_ver = 0;
-	ti->keep_flows = false;
 	get_random_bytes(&ti->hash_seed, sizeof(u32));
 
 	return ti;
@@ -481,9 +480,6 @@ void table_instance_flow_flush(struct flow_table *table,
 {
 	int i;
 
-	if (ti->keep_flows)
-		return;
-
 	for (i = 0; i < ti->n_buckets; i++) {
 		struct hlist_head *head = &ti->buckets[i];
 		struct hlist_node *n;
@@ -603,8 +599,6 @@ static void flow_table_copy_flows(struct table_instance *old,
 						 lockdep_ovsl_is_held())
 				table_instance_insert(new, flow);
 	}
-
-	old->keep_flows = true;
 }
 
 static struct table_instance *table_instance_rehash(struct table_instance *ti,

net/openvswitch/flow_table.h

@@ -53,7 +53,6 @@ struct table_instance {
 	struct rcu_head rcu;
 	int node_ver;
 	u32 hash_seed;
-	bool keep_flows;
 };
 
 struct flow_table {