[llvm] [MC] Fix MCLFI coding style. NFC (PR #228301)

[Fangrui Song via llvm-commits]

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@@ -24,18 +24,18 @@
 #include "llvm/Support/CommandLine.h"
 #include "llvm/TargetParser/Triple.h"
 
-static const char NoteNamespace[] = "LFI";
+using namespace llvm;
 
-static constexpr unsigned X86BundleSize = 32;
+const char NoteNamespace[] = "LFI";
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MaskRay wrote:

namespace-scope const variables are already internal linkage, no need for `static `

https://github.com/llvm/llvm-project/pull/228301