[docs] Mention --discard-locals/--discard-all change for llvm-strip

PR #130704 updated llvm-strip as well.

Suggested by @nga888

Pull Request: https://github.com/llvm/llvm-project/pull/131491
diff --git a/llvm/docs/CommandGuide/llvm-strip.rst b/llvm/docs/CommandGuide/llvm-strip.rst
index b077799..b4d6dc0 100644
--- a/llvm/docs/CommandGuide/llvm-strip.rst
+++ b/llvm/docs/CommandGuide/llvm-strip.rst
@@ -37,9 +37,10 @@
 
 .. option:: --discard-all, -x
 
- Remove most local symbols from the output. Different file formats may limit
- this to a subset of the local symbols. For example, file and section symbols in
- ELF objects will not be discarded. Additionally, remove all debug sections.
+ Remove most local symbols not referenced by relocations from the output.
+ Different file formats may limit this to a subset of the local symbols. For
+ example, file and section symbols in ELF objects will not be discarded.
+ Additionally, remove all debug sections.
 
 .. option::  --enable-deterministic-archives, -D
 
@@ -152,7 +153,7 @@
 
 .. option:: --discard-locals, -X
 
- Remove local symbols starting with ".L" from the output.
+ Remove local symbols starting with ".L" not referenced by relocations from the output.
 
 .. option:: --keep-file-symbols
 
diff --git a/llvm/docs/ReleaseNotes.md b/llvm/docs/ReleaseNotes.md
index 111cdb7..1a948a4 100644
--- a/llvm/docs/ReleaseNotes.md
+++ b/llvm/docs/ReleaseNotes.md
@@ -169,7 +169,8 @@
 
 * 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))
 
 Changes to LLDB
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