[llvm] [llvm-objcopy] Add --skip-symbol and --skip-symbols options (PR #80873)

[Fangrui Song via llvm-commits]

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@@ -464,6 +464,19 @@ them.
  Read a list of symbols from <filename> and change their visibility to the
  specified value. Visibility values: default, internal, hidden, protected.
 
+.. option:: --skip-symbol <symbol>
+
+ Do not change the parameters of symbol ``<symbol>`` when executing other
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MaskRay wrote:

Should this mention that this does not prevent removing symbols?

https://github.com/llvm/llvm-project/pull/80873