message: Add BatchMatMulV2 to auto_mixed_precision whitelist
diff: @@ -63,6 +63,7 @@ class AutoMixedPrecisionLists {
  auto list = gtl::FlatSet<string> {
  #if CUDA_VERSION >= 9010 // Fp16 BatchMatMul is slow before CUDA 9.1.
  "BatchMatMul",
  + "BatchMatMulV2",
  #endif
  "BlockLSTM", "BlockLSTMGrad", "Conv2D", "Conv2DBackpropFilter",
  "Conv2DBackpropInput",
  