[llvm] [DevPolicy] Add guidelines for fuzzer-generated issue reports (PR #112372)

[Antonio Frighetto via llvm-commits]

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@@ -853,6 +853,69 @@ their patch with every possible configuration.
 * 3rd step: If Galina could not help you, please escalate to the
   `Infrastructure Working Group <mailto:iwg at llvm.org>`_.
 
+Guidelines for fuzzer-generated issues
+--------------------------------------
+
+Fuzzing is a valuable tool for finding compiler bugs, and the LLVM project
+welcomes fuzzer-generated test cases. However, some additional guidelines
+should be followed to make such reports maximally useful.
----------------
antoniofrighetto wrote:

How about the following?
```suggestion
Fuzzing is a valuable technique for finding bugs, including those in software like compilers. The LLVM project
welcomes fuzzer-generated test cases, however, some additional guidelines
should be followed to make such reports maximally useful.
```

https://github.com/llvm/llvm-project/pull/112372