fix(block): use correct index for interrupt

Commit d8c2714 (refactor: use VirtioInterrupt in VirtIO devices) which
refactored devices to use new VirtioInterrupt type introduced a bug
with the index used to trigger a queue interrupt. Instead of using the
actual queue index, we were using the index of the used descriptor.

Signed-off-by: Babis Chalios <[email protected]>

Author: bchalios

src/vmm/src/devices/virtio/block/virtio/device.rs

@@ -397,7 +397,7 @@ impl VirtioBlock {
 
         if queue.prepare_kick() {
             interrupt
-                .trigger(VirtioInterruptType::Queue(index))
+                .trigger(VirtioInterruptType::Queue(0))
                 .unwrap_or_else(|_| {
                     block_metrics.event_fails.inc();
                 });