virtio: Port codebase to the latest virtio-queue version

The new virtio-queue version introduced some breaking changes which need
to be addressed so that Cloud Hypervisor can still work with this
version.

The most important change is about removing a handle to the guest memory
from the Queue, meaning the caller has to provide the guest memory
handle for multiple methods from the QueueT trait.

One interesting aspect is that QueueT has been widely extended to
provide every getter and setter we need to access and update the Queue
structure without having direct access to its internal fields.

This patch ports all the virtio and vhost-user devices to this new crate
definition. It also updates both vhost-user-block and vhost-user-net
backends based on the updated vhost-user-backend crate. It also updates
the fuzz directory.

Signed-off-by: Sebastien Boeuf <sebastien.boeuf@intel.com>

virtio-devices/src/lib.rs

@@ -160,7 +160,7 @@ impl TryInto<rate_limiter::RateLimiter> for RateLimiterConfig {
 /// to a host pointer and verify that the provided size define a valid
 /// range within a single memory region.
 /// Return None if it is out of bounds or if addr+size overlaps a single region.
-pub fn get_host_address_range<M: GuestMemory>(
+pub fn get_host_address_range<M: GuestMemory + ?Sized>(
     mem: &M,
     addr: GuestAddress,
     size: usize,