[clang] [lldb] [WebAssembly][Clang] Give wasm tables their own type in clang AST (PR #205817)

[Hood Chatham via cfe-commits]

hoodmane wrote:

Yeah I'm planning to do more, this is just a clean chunk of it. My idea is that table declarations should change to `__externref table[] __attribute((wasmtable))`.

> I thought Wasm tables were getting their own TargetExt type in LLVM IR.

Right, I suppose I should call it clang ast. I changed the title.

Probably they should get their own type in IR? But the pointer decay in clang AST is causing me more problems.

https://github.com/llvm/llvm-project/pull/205817