message: Remove TF_NCCL_VERSION from Dockerfile.gpu.ppc64le
  Now NCCL2 is available in open source and TensorFlow is building
  with it as the default there is no need to force the version to 1
diff: @@ -28,6 +28,3 @@ ENV TF_NEED_CUDA 1
  ENV TF_CUDA_COMPUTE_CAPABILITIES 3.0
  ENV TF_CUDA_VERSION 9.2
  ENV CUDA_TOOLKIT_PATH /usr/local/cuda-9.2
  -
  -# TODO get NCCL 2 in the docker image
  -ENV TF_NCCL_VERSION 1
  