xenapi: support xenapi 5.6.0 headers

* src/xenapi/xenapi_driver.c (xenapiDomainGetInfo): Avoid using
XEN_VM_POWER_STATE_UNKNOWN, which disappeared in newer xenapi.
* src/xenapi/xenapi_utils.c (mapPowerState): Likewise.

src/xenapi/xenapi_driver.c

@@ -966,7 +966,7 @@ xenapiDomainGetInfo (virDomainPtr dom, virDomainInfoPtr info)
         vm = vms->contents[0];
         xen_vm_get_memory_static_max(session, &maxmem, vm);
         info->maxMem = (maxmem / 1024);
-        enum xen_vm_power_state state = XEN_VM_POWER_STATE_UNKNOWN;
+        enum xen_vm_power_state state = XEN_VM_POWER_STATE_UNDEFINED;
         xen_vm_get_power_state(session, &state, vm);
         info->state = mapPowerState(state);
         xen_vm_get_record(session, &record, vm);

src/xenapi/xenapi_utils.c

@@ -344,11 +344,10 @@ mapPowerState(enum xen_vm_power_state state)
     case XEN_VM_POWER_STATE_RUNNING:
         virState = VIR_DOMAIN_RUNNING;
         break;
-    case XEN_VM_POWER_STATE_UNKNOWN:
     case XEN_VM_POWER_STATE_UNDEFINED:
-        virState = VIR_DOMAIN_NOSTATE;
-        break;
     default:
+        /* Includes XEN_VM_POWER_STATE_UNKNOWN from libxenserver
+         * 5.5.0, which is gone in 5.6.0.  */
         virState = VIR_DOMAIN_NOSTATE;
         break;
     }