[clang] [clang-tools-extra] [NFC] Add explicit #include llvm-config.h where its macros are used, clang part. (PR #107301)

[Nikita Popov via cfe-commits]

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@@ -15,6 +15,7 @@
 #include "clang/Driver/InputInfo.h"
 #include "clang/Driver/Options.h"
 #include "clang/Driver/SanitizerArgs.h"
+#include "llvm/Config/llvm-config.h" // for LLVM_HOST_TRIPLE
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nikic wrote:

Possibly we should not have the include for cases like this, where the macro is used directly, not in `#if` and will fail the build when missing?

https://github.com/llvm/llvm-project/pull/107301