docs: networking: Update connection tracking offload sysctl parameters

Document the following connection offload configuration parameters:
- nf_flowtable_tcp_timeout
- nf_flowtable_tcp_pickup
- nf_flowtable_udp_timeout
- nf_flowtable_udp_pickup
Signed-off-by: Oz Shlomo <ozsh@nvidia.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>

Documentation/networking/nf_conntrack-sysctl.rst

@@ -177,3 +177,27 @@ nf_conntrack_gre_timeout_stream - INTEGER (seconds)
 
 	This extended timeout will be used in case there is an GRE stream
 	detected.
+
+nf_flowtable_tcp_timeout - INTEGER (seconds)
+        default 30
+
+        Control offload timeout for tcp connections.
+        TCP connections may be offloaded from nf conntrack to nf flow table.
+        Once aged, the connection is returned to nf conntrack with tcp pickup timeout.
+
+nf_flowtable_tcp_pickup - INTEGER (seconds)
+        default 120
+
+        TCP connection timeout after being aged from nf flow table offload.
+
+nf_flowtable_udp_timeout - INTEGER (seconds)
+        default 30
+
+        Control offload timeout for udp connections.
+        UDP connections may be offloaded from nf conntrack to nf flow table.
+        Once aged, the connection is returned to nf conntrack with udp pickup timeout.
+
+nf_flowtable_udp_pickup - INTEGER (seconds)
+        default 30
+
+        UDP connection timeout after being aged from nf flow table offload.