message: Fix header inclusion check in NCCL.
diff: @@ -77,6 +77,8 @@ cc_library(
  # http://docs.bazel.build/versions/master/be/c-cpp.html#hdrs).
  # Files in src/ which #include "nccl.h" load it from there rather than
  # from the virtual includes directory.
  + "src/collectives.h",
  + "src/collectives/collectives.h",
  "src/nccl.h",
  ],
  hdrs = ["src/nccl.h"],
  