Thread-pool support for TX symbol processing.
This MR adds thread-pool support for TX symbol processing. It allows modulation
/mapping/layer-precoding to run in parallel and offers a speedup of around 3
compared to single-thread execution. This is particularly important for large
bandwidths and 4 or more TX antenna ports where the precoding operation is quite
computationally-intensive.
Please see the description of !3489 for the performance comparison results and
the nr_dlsim timing measurements.
Jaroslava Fiedlerova
8583689349