[clang] [llvm] [CMake][NFC] Don't use uninitialized LLVM_REQUIRES_* (PR #175554)

[Nikita Popov via cfe-commits]

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@@ -3,9 +3,5 @@ add_library(MathTest STATIC
 
 target_include_directories(MathTest PUBLIC "${CMAKE_CURRENT_SOURCE_DIR}/../include")
 
-if(NOT LLVM_REQUIRES_RTTI)
-  target_compile_options(MathTest PUBLIC -fno-rtti)
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nikic wrote:

To preserve the previous behavior here, shouldn't we be always setting the option?

https://github.com/llvm/llvm-project/pull/175554