message: Modified mkl concat op to also use eigen when input dimensions is 2.
diff: @@ -216,7 +216,7 @@ class MklConcatOp : public OpKernel {
  else
  are_all_mkl_inputs = false;
  - if (s_dims != 4 && s_dims != 2) invoke_eigen = true;
  + if (s_dims != 4) invoke_eigen = true;
  ++i;
  }
  