memory: MemoryRegion: use /machine as default owner

This will be added (after QOMification) as the QOM parent.

Reviewed-by: Peter Crosthwaite <peter.crosthwaite@xilinx.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
diff --git a/vl.c b/vl.c
index 41ddcd26..88feeab 100644
--- a/vl.c
+++ b/vl.c
@@ -3986,12 +3986,11 @@
         exit(1);
     }
 
-    cpu_exec_init_all();
-
     current_machine = MACHINE(object_new(object_class_get_name(
                           OBJECT_CLASS(machine_class))));
     object_property_add_child(object_get_root(), "machine",
                               OBJECT(current_machine), &error_abort);
+    cpu_exec_init_all();
 
     if (machine_class->hw_version) {
         qemu_set_version(machine_class->hw_version);