migration: max_postcopy_bandwidth is a size parameter

So make everything that uses it uint64_t no int64_t.

Signed-off-by: Juan Quintela <quintela@redhat.com>
Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
Message-Id: <20230504113841.23130-2-quintela@redhat.com>
3 files changed