[clang] Disable LIBCXX_INCLUDE_BENCHMARKS in Fuchsia cmake (PR #116446)

[Caslyn Tonelli via cfe-commits]

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@@ -31,6 +31,7 @@ set(LLVM_STATIC_LINK_CXX_STDLIB ON CACHE BOOL "")
 set(LLVM_USE_RELATIVE_PATHS_IN_FILES ON CACHE BOOL "")
 set(LLDB_ENABLE_CURSES OFF CACHE BOOL "")
 set(LLDB_ENABLE_LIBEDIT OFF CACHE BOOL "")
+set(LIBCXX_INCLUDE_BENCHMARKS OFF CACHE BOOL "")
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Caslyn wrote:

Also - PTAL @ https://github.com/llvm/llvm-project/pull/115361#issuecomment-2480526628.  

https://github.com/llvm/llvm-project/pull/116446