[llvm] [docs] Mention --discard-locals/--discard-all change for llvm-strip (PR #131491)

[Fangrui Song via llvm-commits]

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@@ -165,7 +165,8 @@ Changes to the LLVM tools
 
 * llvm-objcopy now supports the `--update-section` flag for intermediate Mach-O object files.
 * llvm-strip now supports continuing to process files on encountering an error.
-* In llvm-objcopy's ELF port, `--discard-locals` and `--discard-all` now allow and preserve symbols referenced by relocations.
+* In llvm-objcopy/llvm-strip's ELF port, `--discard-locals` and `--discard-all` now allow and preserve symbols referenced by relocations.
+  (`#47468 <https://github.com/llvm/llvm-project/issues/47468>`_).
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MaskRay wrote:

Thanks for spotting this! I thought I was writing reST..

https://github.com/llvm/llvm-project/pull/131491