Remove useless NULL test from cyttsp4_watchdog_timer().
Signed-off-by: Wei Yongjun <yongjun_wei@trendmicro.com.cn>
Acked-by: Ferruh Yigit <fery@cypress.com>
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>