Wasm: support tail calls in CallingConv::SwiftTail#12648

MaxDesiatov wants to merge 2 commits intoswiftlang:stable/21.xswiftlang/llvm-project:stable/21.xfrom

MaxDesiatov:maxd/wasm-tail-callMaxDesiatov/llvm-project:maxd/wasm-tail-callCopy head branch name to clipboard