Log Message:
uhd: update to 4.1.0.4

With UHD 4.0, RFNoC has undergone a major overhaul for improved usability,
performance, and compatibility with tools like GNU Radio.

Improved Radio Performance
  Increase channel bandwidth to 250 MSPS and beyond.
  Flexible bus width to increase throughput.
  Static routing for lower latency and higher throughput
  Updates to the NOC shell layer for improved latency and throughput.
FPGA Design Flow Enhancements
  Ability to scale to a larger number of user-defined blocks.
  Reduced FPGA resource utilization in many instances.
More Flexibility
  Architectural flexibility enables users to make more design tradeoffs.
  Allows the user to balance flexibility, resource utilization, and performance.
Improved User Experience
 Improved documentation with a full RFNoC Specification
 Power calibration utility API (requires external calibration reference)
 Python API enhancements with full Python 3 support.
 Stability improvements from new automated testing infrastructure.
 Use embedded series radios without programming the ARM processing with
   "Network Mode" over the RJ45