[llvm] [llvm-objcopy][COFF] Update WinCFGuard section contents after stripping (PR #153322)

[Evgenii Kudriashov via llvm-commits]

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@@ -1,8 +1,12 @@
+# .gfids$y, .giats$y and .gljmp$y cf-guard sections consist of .symidx
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e-kud wrote:

Folded them together.

https://github.com/llvm/llvm-project/pull/153322