[clang] [z.OS] fix strnlen() usage in Context.cpp available on z/OS (PR #160339)

[Zibi Sarbinowski via cfe-commits]

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@@ -18,6 +18,7 @@
 #include "clang/AST/ASTLambda.h"
 #include "clang/AST/Expr.h"
 #include "clang/Basic/TargetInfo.h"
+#include "llvm/Support/SystemZ/zOSSupport.h"
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zibi2 wrote:

Thank you for suggestion.

This header is included in 1/2 a dozen places and it was not removed so far but when it does I will look into your suggestion.

https://github.com/llvm/llvm-project/pull/160339