bugfix: Add guard for fp4/fp8 related include headers (#1376)

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## 📌 Description

Fix compilation issue of `cutlass_utils.cuh`

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Author: yzh119

include/flashinfer/cutlass_utils.cuh

@@ -16,6 +16,8 @@
 #ifndef FLASHINFER_CUTLASS_UTILS_CUH_
 #define FLASHINFER_CUTLASS_UTILS_CUH_
 
+#include <cuda_fp8.h>
+
 #include "cute/tensor.hpp"
 #include "cutlass/cutlass.h"
 #include "cutlass/epilogue/collective/collective_builder.hpp"
@@ -39,7 +41,6 @@
 #include "cutlass/util/reference/device/tensor_compare.h"
 #include "cutlass/util/reference/device/tensor_fill.h"
 #include "cutlass/util/tensor_view_io.h"
-
 #if defined(FLASHINFER_ENABLE_FP4_E2M1)
 #include <cuda_fp4.h>
 #endif