[lld] [LLD] Add CLASS syntax to SECTIONS (PR #95323)

[Fangrui Song via llvm-commits]

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@@ -137,6 +137,25 @@ struct OutputDesc final : SectionCommand {
   }
 };
 
+// A list of input sections that can be referenced in output descriptions.
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MaskRay wrote:

// This represents a `CLASS(class_name) { ... }` that can be referenced by output section descriptions. If referenced more than once, the sections can be spilled to the next reference like --enable-non-contiguous-regions.

https://github.com/llvm/llvm-project/pull/95323