release/20.x: [llvm-objcopy][ReleaseNotes] Fix prints wrong path when dump-section output path doesn't exist llvm#125345 (llvm#126607)

Add release note for llvm-objcopy fixing prints wrong path when
dump-section output path doesn't exist in llvm#125345

Author: AmrDeveloper

llvm/docs/ReleaseNotes.md

@@ -460,6 +460,8 @@ Changes to the LLVM tools
   `--localize-symbol`, `--localize-symbols`,
   `--skip-symbol`, `--skip-symbols`.
 
+* llvm-objcopy now prints the correct file path in the error message when the output file specified by `--dump-section` cannot be opened.
+
 Changes to LLDB
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