This commit moves the cranelift tests and tools from the `wabt` crate on
crates.io (which compiles the wabt C++ codebase) to the `wat` crate on
crates.io which is a Rust parser for the `*.wat` format. This was
motivated by me noticing that release builds on Windows are ~5 minutes
longer than Linux builds, and local timing graphs showed that `wabt-sys`
was by far the longest build step in the build process.
This commit changes the `clif-util` binary where the `--enable-simd`
flag is no longer respected with the text format as input, since the
`wat` crate has no feature gating. This was already sort of not
respected, though, since `--enable-simd` wasn't consulted for binary
inputs which `clif-util` supports as well. If this isn't ok though then
it should be ok to close this PR!