message: Use attach and detach methods - we can build with latest poplar again.
  Summary: Fixes T3557
  Test Plan: All tests pass.
  Reviewers: jamesn
  Maniphest Tasks: T3557
diff: @@ -314,7 +314,7 @@ Status PoplarExecutor::InitializePoplarDevice(
  "Unrecognized poplar device type for ordinal %d: %d", ordinal_, type);
  }
  - if (!poplar_device_.tryToAcquire()) {
  + if (!poplar_device_.attach()) {
  return xla::ResourceExhausted(
  "Unable to acquire poplar device type for ordinal %d", ordinal_);
  }
  @@ -349,7 +349,7 @@ Status PoplarExecutor::InitializePoplarDevice(
  Status PoplarExecutor::ClosePoplarDevice(void* device) {
  if (device == active_xla_device_) {
  - poplar_device_.release();
  + poplar_device_.detach();
  active_xla_device_ = nullptr;
  }
  return Status::OK();
  