[llvm] [readtapi] Setup simple stubify support (PR #76075)

[Cyndy Ishida via llvm-commits]

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@@ -27,6 +31,10 @@ using namespace llvm;
 using namespace MachO;
 using namespace object;
 
+#if !defined(PATH_MAX)
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cyndyishida wrote:

Right, `PATH_MAX` is not defined for windows. 
For tapi's use case I picked the default value defined in macOS sdk's `syslimits.h`, to default on, which does differ from Support/Unix.inc's value.

https://github.com/llvm/llvm-project/pull/76075