Fix compile error

test=develop

paddle/fluid/platform/cuda_helper_test.cu

@@ -93,7 +93,7 @@ TEST(CudaAtomic, float16) {
 
 // unalignment of uint8
 void TestUnalign(size_t num, const int shift_bit) {
-  PADDLE_ENFORCE(num % 2 == 0, "must be a multiple of 2");
+  ASSERT_EQ(num % 2, 0);
   float16 *in1, *in2, *out;
   float16 *d_in1, *d_in2;
   size_t size = sizeof(uint8_t) * (num + shift_bit);