[lld] [LLD][ELF] Add `-z execute-only-report` that checks PURECODE section flags (PR #128883)

[Csanád Hajdú via llvm-commits]

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@@ -323,6 +324,7 @@ template <class ELFT> void Writer<ELFT>::run() {
   // finalizeSections does that.
   finalizeSections();
   checkExecuteOnly();
+  checkExecuteOnlyReport();
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Il-Capitano wrote:

I didn't do this yet, because I think that `checkExecuteOnly` and `checkExecuteOnlyReport` aside from the similar naming do different things and they should be separate.

https://github.com/llvm/llvm-project/pull/128883