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

[James Henderson via llvm-commits]

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@@ -0,0 +1,75 @@
+# Bail out if a section consisting of symidx has unexpected format for patching
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jh7370 wrote:

Nit: llvm-objcopy tests (along with most new LLVM binutils testing) uses double comment markers (i.e. `##` here) for comments, to help distinguish them from `RUN` and `CHECK` lines etc.

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