[lld] [LLD][COFF] Emit tail merge pdata for delay load thunks on ARM64EC (PR #116810)

[Jacek Caban via llvm-commits]

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@@ -395,6 +395,7 @@ class TailMergePDataChunkX64 : public NonSectionChunk {
   }
 
   size_t getSize() const override { return 3 * sizeof(uint32_t); }
+  MachineTypes getMachine() const override { return AMD64; }
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cjacek wrote:

ARM64EC targets require an additional operation in `Writer::mergeSections` to separate ARM and x86 chunks. Other targets do not consider the machine type of `.pdata` entries, so this was unnecessary prior to this PR.

I added `getMachine` to `TailMergeUnwindInfoX64` for consistency, though it could be skipped.

https://github.com/llvm/llvm-project/pull/116810