[clang] [CUDA] add wrapper header for libc++'s __utlility/declval.h (PR #148918)

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``````````bash
git-clang-format --diff HEAD~1 HEAD --extensions h -- clang/lib/Headers/cuda_wrappers/__utility/declval.h
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View the diff from clang-format here.
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``````````diff
diff --git a/clang/lib/Headers/cuda_wrappers/__utility/declval.h b/clang/lib/Headers/cuda_wrappers/__utility/declval.h
index b16311e84..a8434e360 100644
--- a/clang/lib/Headers/cuda_wrappers/__utility/declval.h
+++ b/clang/lib/Headers/cuda_wrappers/__utility/declval.h
@@ -11,20 +11,17 @@ _LIBCPP_BEGIN_NAMESPACE_STD
 // Suppress deprecation notice for volatile-qualified return type resulting
 // from volatile-qualified types _Tp.
 _LIBCPP_SUPPRESS_DEPRECATED_PUSH
-template <class _Tp>
-__attribute__((device))
-_Tp&& __declval(int);
-template <class _Tp>
-__attribute__((device))
-_Tp __declval(long);
+template <class _Tp> __attribute__((device)) _Tp &&__declval(int);
+template <class _Tp> __attribute__((device)) _Tp __declval(long);
 _LIBCPP_SUPPRESS_DEPRECATED_POP
 
 template <class _Tp>
-__attribute__((device))
-_LIBCPP_HIDE_FROM_ABI decltype(std::__declval<_Tp>(0)) declval() _NOEXCEPT {
+__attribute__((device)) _LIBCPP_HIDE_FROM_ABI decltype(std::__declval<_Tp>(0))
+declval() _NOEXCEPT {
   static_assert(!__is_same(_Tp, _Tp),
                 "std::declval can only be used in an unevaluated context. "
-                "It's likely that your current usage is trying to extract a value from the function.");
+                "It's likely that your current usage is trying to extract a "
+                "value from the function.");
 }
 
 _LIBCPP_END_NAMESPACE_STD

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https://github.com/llvm/llvm-project/pull/148918