wasi: switch to use wasmtime-wiggle for wiggle integration

Cargo.lock

@@ -2567,6 +2567,7 @@ dependencies = [
  "wasi-common",
  "wasmtime",
  "wasmtime-runtime",
+ "wasmtime-wiggle",
  "wig",
  "wiggle",
 ]

crates/wasi/Cargo.toml

@@ -19,6 +19,7 @@ wasmtime = { path = "../wasmtime", version = "0.18.0", default-features = false
 wasmtime-runtime = { path = "../runtime", version = "0.18.0" }
 wig = { path = "../wasi-common/wig", version = "0.18.0" }
 wiggle = { path = "../wiggle", version = "0.18.0" }
+wasmtime-wiggle = { path = "../wiggle/wasmtime", version = "0.18.0" }
 
 [badges]
 maintenance = { status = "actively-developed" }

crates/wasi/src/lib.rs

@@ -6,7 +6,7 @@ pub use wasi_common::{WasiCtx, WasiCtxBuilder};
 
 // Defines a `struct Wasi` with member fields and appropriate APIs for dealing
 // with all the various WASI exports.
-wig::define_wasi_struct_for_wiggle!("phases/snapshot/witx/wasi_snapshot_preview1.witx");
+wasmtime_wiggle::define_struct_for_wiggle!("phases/snapshot/witx/wasi_snapshot_preview1.witx");
 
 pub fn is_wasi_module(name: &str) -> bool {
     // FIXME: this should be more conservative, but while WASI is in flux and