vmm: Add device_id field to NUMA configuration

Add an optional device_id string field to NumaConfig for identifying
PCI devices associated with a NUMA node. This is used by the Generic
Initiator support to map devices to their proximity domain.

Update OpenAPI spec (cloud-hypervisor.yaml) to include the
new device_id field in the NumaConfig schema.

The device_id is optional and parsed from the --numa parameter:
  --numa "device_id=<device_id>,distances=[...],..."

The optional field is accepted but not used.

Signed-off-by: Saravanan D <saravanand@crusoe.ai>

vmm/src/api/openapi/cloud-hypervisor.yaml

@@ -1203,6 +1203,8 @@ components:
           items:
             type: integer
             format: int32
+        device_id:
+          type: string
 
     VmResize:
       type: object