We want to place non-qmp stubs in there, so let's rename it. While at
it, put it into the MAINTAINERS file under "Memory devices".

Message-ID: <20230926185738.277351-8-david@redhat.com>
Reviewed-by: Maciej S. Szmigiero <maciej.szmigiero@oracle.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: David Hildenbrand <david@redhat.com>