Currently, LxIP peers need a lot of RAM (the simple test-client/server for the
nic_router test need at least 28 MB per component). As the nic_router test
previously used 6 instances of such components and a lot of other components,
it had issues with insufficient RAM on some platforms. By using two new
LwIP-based UDP tests instead, we save more than 100 MB.
Ref #2543