migration: purge MigrationState from public interface

Move remaining MigrationState references from the public file
misc.h to the private file migration.h.

Signed-off-by: Steve Sistare <steven.sistare@oracle.com>
Link: https://lore.kernel.org/r/1710179338-294359-12-git-send-email-steven.sistare@oracle.com
Signed-off-by: Peter Xu <peterx@redhat.com>
2 files changed