[lld] [llvm] WebAssembly: Move runtime libcall setting out of TargetLowering (PR #142624)

[Matt Arsenault via llvm-commits]

arsenm wrote:

### Merge activity

* **Jun 16, 1:44 AM UTC**: A user started a stack merge that includes this pull request via [Graphite](https://app.graphite.dev/github/pr/llvm/llvm-project/142624).


https://github.com/llvm/llvm-project/pull/142624