[clang] [llvm] [SystemZ][z/OS] Add new openFileForReadBinary function, and pass IsText parameter to getBufferForFile (PR #111723)

[Sean Perry via cfe-commits]

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@@ -302,6 +305,17 @@ class RealFileSystem : public FileSystem {
     return Storage;
   }
 
+  ErrorOr<std::unique_ptr<File>> openFileForRead(const Twine &Name,
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perry-ca wrote:

Thanks, Could you mark this as static.

https://github.com/llvm/llvm-project/pull/111723