The ProxyState is only used by the IPAProxy, so it should remain inside
that scope. This helps clarify the usage, and improves the
documentation by bringing the (future) ProxyState documentation into the
class.
Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Kieran Bingham <kieran.bingham@ideasonboard.com>