message: backout setting poplar engine option
  Summary: This reverts commit
  Test Plan: revert-hammer
  Reviewers:
  Subscribers:
diff: @@ -1675,12 +1675,6 @@ Status PoplarExecutor::ConfigurePoplarDevice(const IpuOptions& cfg) {
  option_flags_.set("exchange.enablePrefetch", "true");
  }
  - option_flags_.set(
  - "target.maxStreamCallbackThreadsPerNumaNode",
  - PoplarXlaFlags::Get().max_infeed_threads > 0
  - ? std::to_string(PoplarXlaFlags::Get().max_infeed_threads)
  - : "auto");
  -
  for (const auto& opt : current_config_.compilation_options()) {
  option_flags_.set(opt.option(), opt.value());
  }
  