[clang-tools-extra] [libc] Refactor scanf reader to match printf (PR #66023)

[Joseph Huber via cfe-commits]

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@@ -126,6 +126,10 @@ set(TARGET_LIBC_ENTRYPOINTS
     libc.src.stdio.snprintf
     libc.src.stdio.vsprintf
     libc.src.stdio.vsnprintf
+    #TODO: Check if scanf can be enabled on aarch64
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jhuber6 wrote:

Seems like this should be tested first.

https://github.com/llvm/llvm-project/pull/66023