[llvm] [symbolizer] Update Release notes. (PR #142951)

[James Henderson via llvm-commits]

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@@ -36,6 +36,9 @@ Here are some of those differences:
 -  ``llvm-addr2line`` parses options from the environment variable
    ``LLVM_ADDR2LINE_OPTS`` instead of from ``LLVM_SYMBOLIZER_OPTS``.
 
+- ``llvm-addr2line`` accepts an address with a '+' prefix ie `+0x00777fff`
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jh7370 wrote:

I'd actually point out what happens when it is used for llvm-symbolizer. If I understand correctly, such a case is treated as a symbol name, so I'd change the second sentence to: `This is treated as a symbol name by ``llvm-symbolizer``.`

https://github.com/llvm/llvm-project/pull/142951