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

Towards
#https://github.com/llvm/llvm-project/issues/134809#issuecomment-2787206873

This change moves WasmSym from a static global struct to an instance
owned by Ctx, allowing it to be reset cleanly between linker runs. This
enables safe support for multiple invocations of wasm-ld within the same
process

Changes done 

- Converted WasmSym from a static struct to a regular struct with
instance members.

- Added a std::unique_ptr<WasmSym> wasmSym field inside Ctx.

- Reset wasmSym in Ctx::reset() to clear state between links.

- Replaced all WasmSym:: references with ctx.wasmSym->.

- Removed global symbol definitions from Symbols.cpp that are no longer
needed.

Clearing wasmSym in ctx.reset() ensures a clean slate for each link
invocation, preventing symbol leakage across runs—critical when using
wasm-ld/lld as a reentrant library where global state can cause subtle,
hard-to-debug errors.

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Co-authored-by: Vassil Vassilev <v.g.vassilev@gmail.com>

0 files changed, 0 insertions, 0 deletions