[llvm] [DirectX] Add `extract-section` to `llvm-objcopy` and implement it for `DXContainer` (PR #154804)

[James Henderson via llvm-commits]

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@@ -69,6 +69,11 @@ def strip_sections
     : Flag<["--"], "strip-sections">,
       HelpText<"Remove all section headers and all section data not within segments">;
 
+defm extract_section
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jh7370 wrote:

Options in this file should be ordered alphabetically.

https://github.com/llvm/llvm-project/pull/154804