Document DT binding for static (non-configurable) funnel and give an
example for it.
Cc: Mathieu Poirier <mathieu.poirier@xxxxxxxxxx>
Cc: Suzuki K Poulose <suzuki.poulose@xxxxxxx>
Cc: Wanglai Shi <shiwanglai@xxxxxxxxxxxxx>
Signed-off-by: Leo Yan <leo.yan@xxxxxxxxxx>