Conditional dependencies for WASM are not applied for target wasm32-wasi

[ldamia]

This is caused by the condition all(target_arch = "wasm32", target_os = "unknown") in Cargo.toml, which does not apply to target wasm32-wasi. I do not know if this is intentional but if so, perhaps a conditional compile_error! would make the error messages more understandable.