Update to rustix 0.33.6. (#4022)

Relevant to Wasmtime, this fixes undefined references to `utimensat` and
`futimens` on macOS 10.12 and earlier. See bytecodealliance/rustix#157
for details.

It also contains a fix for s390x which isn't currently needed by Wasmtime
itself, but which is needed to make rustix's own testsuite pass on s390x,
which helps people packaging rustix for use in Wasmtime. See
bytecodealliance/rustix#277 for details.

Cargo.lock

@@ -2500,9 +2500,9 @@ dependencies = [
 
 [[package]]
 name = "rustix"
-version = "0.33.5"
+version = "0.33.6"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "03627528abcc4a365554d32a9f3bbf67f7694c102cfeda792dc86a2d6057cc85"
+checksum = "7ac32d9fc97153ca55305284cb6c2dcbb84e1fc6d7ac13392cea02222f2d8741"
 dependencies = [
  "bitflags",
  "errno",