migration: Use vmstate_register_any()

This are the easiest cases, where we were already using
VMSTATE_INSTANCE_ID_ANY.

Reviewed-by: Stefan Berger <stefanb@linux.ibm.com>
Signed-off-by: Juan Quintela <quintela@redhat.com>
Message-ID: <20231020090731.28701-3-quintela@redhat.com>
11 files changed