[clang] [compiler-rt] [libcxx] [libunwind] [llvm] [openmp] [cmake] switch to CMake's native `check_{compiler,linker}_flag` (PR #96171)

[via cfe-commits]

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@@ -1,28 +0,0 @@
-include(CheckLinkerFlag OPTIONAL)
-
-if (COMMAND check_linker_flag)
-  macro(llvm_check_linker_flag)
-    check_linker_flag(${ARGN})
-  endmacro()
-else()
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h-vetinari wrote:

... and here

https://github.com/llvm/llvm-project/pull/96171