[llvm] [llvm] Disable HandleLLVMOptions in runtimes mode (PR #73031)

[Joseph Huber via llvm-commits]

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@@ -151,9 +151,11 @@ endif()
 # Avoid checking whether the compiler is working.
 set(LLVM_COMPILER_CHECKED ON)
 
+# This can be used to detect whether we're in the runtimes build.
+set(LLVM_RUNTIMES_BUILD ON)
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jhuber6 wrote:

Doesn't hurt to set it earlier, but I can remove it to make it cleaner.

https://github.com/llvm/llvm-project/pull/73031