Created by: chenwhql

• original writing:

PADDLE_ENFORCE_EQ(	    
        ctx->HasInput("X"), true,
        platform::errors::NotFound("Input(X) of MulOp should not be null."));

• new writing:

OP_INOUT_CHECK(ctx->HasInput("X"), "Input", "X", "Mul");

• Result:

----------------------
Error Message Summary:
----------------------
NotFoundError: No Input(X) found for dummy operator.
  [Hint: Expected false == true, but received false:0 != true:1.] at (/work/paddle/paddle/fluid/platform/enforce_test.cc:366)