wasip3: descriptor#advise for will-need behaves differently between macos and everything else

[wingo]

On MacOS with wasmtime, filesystem-advice fails:

 Test filesystem-advise failed
  [exit_code] 0 == 1
STDOUT:

STDERR:
fadvise(7, 0, Advice::WillNeed) => file-too-large (error 7)

This test passes on Windows and Ubuntu.

The failing advise call on MacOS would appear to be offset=7 (which is the size of the file), length=0. The error occurs here: https://github.com/WebAssembly/wasi-testsuite/blob/main/tests/rust/wasm32-wasip3/src/bin/filesystem-advise.rs#L54

Is it reasonable to want to make this not issue an error for WontNeed beyond the end of the file? @alexcrichton @sunfishcode @pchickey

[alexcrichton]

Looks like this may be due to this using F_RDADVISE on macOS since posix_fadvise doesn't exist. Given that it's a totally separate syscall I don't know how feasible it would be to canonicalize errors here.