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

[Evgenii Kudriashov via llvm-commits]

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@@ -0,0 +1,75 @@
+# Bail out if a section consisting of symidx has unexpected format for patching
+# its content and updating a check sum. Basically, the expected format is a
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e-kud wrote:

Now `checksum` is everywhere

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