`applehv.Start()` has this line of code:
```
cmd.ExtraFiles = []*os.File{ioEater, ioEater, ioEater}
```
whose purpose is not clear.
The intent may have been to redirect stdin/stdout/stderr to /dev/null in
the child process.
This should be done by setting cmd.Stdin/cmd.Stdout/cmd/Stderr to nil,
which is the case by default.
The way it's done could also cause issues as
`Vfkit.VirtualMachine.Cmd()` sometimes adds files it needs to keep open
to `ExtraFiles`, so at the very least this should be an `append()`
This commit removes this code.
[NO NEW TESTS NEEDED]
Signed-off-by: Christophe Fergeau <cfergeau@redhat.com>
90f69891d7