revise and improve if needed the existing 2-node keywords:

resources/libraries/robot/performance/performance_setup.robot:
Set variables in 2-node circular topology
Set variables in 2-node circular topology with DUT interface model
Set up 2-node performance topology with DUT's NIC model
Set up 2-node-switched performance topology with DUT's NIC model
Set up DPDK 2-node performance topology with DUT's NIC model
Tear down 2-node performance topology
Tear down 2-node performance topology with container
Tear down DPDK 2-node performance topology

resources/libraries/robot/performance/performance_configuration.robot:
Set interfaces in path in 2-node circular topology up
Add PCI devices to DUTs in 2-node single link topology
Add single PCI device to DUTs in 2-node single link topology

resources/libraries/robot/shared/testing_path.robot:
Configure path in 2-node circular topology
Set interfaces in 2-node circular topology up

resources/libraries/robot/shared/default.robot:
Add '${m}' worker threads and '${n}' rxqueues in 2-node single-link circular topology
Add '${m}' worker threads using SMT and '${n}' rxqueues in 2-node single-link circular topology

resources/libraries/robot/tldk/tldk_utils.robot:
Path for 2-node testing is set