[wasm-split] Improve the error message for bad checksums (#5268)
[wasm-split] Improve the error message for bad checksums (#5268)

The previous error message was ambiguous and could easily be interpreted to mean
the opposite of what it meant.
WebAssembly/binaryen,WebAssembly/binaryen,WebAssembly/binaryen,WebAssembly/binaryen,WebAssembly/binaryen