[lld] [wasm-ld] Refactor WasmSym from static globals to per-link context (PR #134970)

[Sam Clegg via llvm-commits]

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@@ -32,6 +32,7 @@ class InputTable;
 class InputGlobal;
 class InputFunction;
 class Symbol;
+struct WasmSym;
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sbc100 wrote:

Is this forward declaration needed?  I'd be surprised if `WasmSym sym{};` would work below with only a forward decl.

https://github.com/llvm/llvm-project/pull/134970