message: Add elu operator to micro mutable op resolver.
diff: @@ -188,6 +188,10 @@ class MicroMutableOpResolver : public MicroOpResolver {
  tflite::Register_DETECTION_POSTPROCESS());
  }
  + TfLiteStatus AddElu() {
  + return AddBuiltin(BuiltinOperator_ELU, tflite::Register_ELU(), ParseElu);
  + }
  +
  TfLiteStatus AddEqual() {
  return AddBuiltin(BuiltinOperator_EQUAL,
  tflite::ops::micro::Register_EQUAL(), ParseEqual);
  