rfnoc: add rx and tx transports, and amend rfnoc_graph

transports:

Transports build on I/O service and implements flow control and
sequence number checking.

The rx streamer subclass extends the streamer implementation to connect
it to the rfnoc graph. It receives configuration values from property
propagation and configures the streamer accordingly. It also implements
the issue_stream_cmd rx_streamer API method.

Add implementation of rx streamer creation and method to connect it to
an rfnoc block.

rfnoc_graph: Cache more connection info, clarify contract

Summary of changes:
- rfnoc_graph stores more information about static connections at the
  beginning. Some search algorithms are replaced by simpler lookups.
- The contract for connect() was clarified. It is required to call
  connect, even for static connections.

1 files changed, 2 insertions, 0 deletions

diff --git a/host/tests/CMakeLists.txt b/host/tests/CMakeLists.txt
index d6ad6d777..1cdb42b96 100644
--- a/host/tests/CMakeLists.txt
+++ b/host/tests/CMakeLists.txt
@@ -55,6 +55,8 @@ set(test_sources
     fe_conn_test.cpp
     rfnoc_node_test.cpp
     link_test.cpp
+    rx_streamer_test.cpp
+    tx_streamer_test.cpp
 )
 
 set(benchmark_sources