[llvm] [llvm-objcopy] Add llvm-objcopy option --set-symbol-visibility (PR #80872)

[Fangrui Song via llvm-commits]

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@@ -93,6 +93,17 @@ defm set_section_type
          "Set the type of section <section> to the integer <type>">,
       MetaVarName<"section=type">;
 
+defm set_symbol_visibility
+    : Eq<"set-symbol-visibility",
+         "Change the visibility of a symbol to the specified type">,
+      MetaVarName<"symbol=visibility_type">;
+defm set_symbols_visibility
+    : Eq<"set-symbols-visibility",
+         "Reads a list of symbols from <filename> and changes their "
+         "visibility to the specified type. Visibility types: default, "
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MaskRay wrote:

We don't use "visibility type". The generic ABI (official spec) uses "visibility attribute" (https://www.sco.com/developers/gabi/latest/ch4.symtab.html) 

https://github.com/llvm/llvm-project/pull/80872