Merge pull request #83755 from MaxDesiatov/wasmkit-cmake
Currently, passing `--wasmkit` to `build-script` also requires `--swiftpm --install-swiftpm` and all of their dependencies (at the very least Dispatch, Foundation, XCTest, Testing, llbuild, swift-build). We can conditionally switch to host SwiftPM when new SwiftPM is not built or installed.
