qemu: hotplug: Properly emit "DEVICE_DELETED" event when unplugging memory

The event needs to be emitted after the last monitor call, so that it's
not possible to find the device in the XML accidentally while the vm
object is unlocked.

Resolves: https://bugzilla.redhat.com/show_bug.cgi?id=1414393

src/qemu/qemu_hotplug.c

@@ -3691,9 +3691,6 @@ qemuDomainRemoveMemoryDevice(virQEMUDriverPtr driver,
     VIR_DEBUG("Removing memory device %s from domain %p %s",
               mem->info.alias, vm, vm->def->name);
 
-    event = virDomainEventDeviceRemovedNewFromObj(vm, mem->info.alias);
-    qemuDomainEventQueue(driver, event);
-
     if (virAsprintf(&backendAlias, "mem%s", mem->info.alias) < 0)
         return -1;
 
@@ -3708,6 +3705,9 @@ qemuDomainRemoveMemoryDevice(virQEMUDriverPtr driver,
     if (rc < 0)
         return -1;
 
+    event = virDomainEventDeviceRemovedNewFromObj(vm, mem->info.alias);
+    qemuDomainEventQueue(driver, event);
+
     if ((idx = virDomainMemoryFindByDef(vm->def, mem)) >= 0)
         virDomainMemoryRemove(vm->def, idx);