[llvm] [llvm-cxxfilt] Add --quote option to quote demangled function names (PR #111871)

[James Henderson via llvm-commits]

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@@ -0,0 +1,12 @@
+// Show that llvm-cxxfilt --quote can emit quoted demangled symbols but not
+// without double-quoting in the case they are already quoted
----------------
jh7370 wrote:

```suggestion
// Show that llvm-cxxfilt --quote can emit quoted demangled symbols but not
// without double-quoting in the case they are already quoted.
```
Nit.

https://github.com/llvm/llvm-project/pull/111871