In qemu_luring_poll_cb() we are not using the cqe peeked from the
CQ ring. We are using io_uring_peek_cqe() only to see if there
are cqes ready, so we can replace it with io_uring_cq_ready().

Signed-off-by: Stefano Garzarella <sgarzare@redhat.com>
Message-id: 20200519134942.118178-1-sgarzare@redhat.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>