We're trying to lock mutex when cdn-dp shutdown, so we need to make
sure the mutex is inited in cdn-dp's probe.
Signed-off-by: NJeffy Chen <jeffy.chen@rock-chips.com>
Reviewed-by: NGuenter Roeck <groeck@chromium.org>
Reviewed-by: NChris Zhong <zyw@rock-chips.com>
Signed-off-by: NChris Zhong <zyw@rock-chips.com>