Input: bcm-keypad - remove unneeded NULL check before clk_disable_unprepare

clk_disable_unprepare() already checks NULL by using IS_ERR_OR_NULL.
Remove unneeded NULL check for kp->clk.
Signed-off-by: Wan Jiabing <wanjiabing@vivo.com>
Link: https://lore.kernel.org/r/20220516085511.10679-1-wanjiabing@vivo.comSigned-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>

drivers/input/keyboard/bcm-keypad.c

@@ -183,8 +183,7 @@ static void bcm_kp_stop(const struct bcm_kp *kp)
 	writel(0xFFFFFFFF, kp->base + KPICR0_OFFSET);
 	writel(0xFFFFFFFF, kp->base + KPICR1_OFFSET);
 
-	if (kp->clk)
-		clk_disable_unprepare(kp->clk);
+	clk_disable_unprepare(kp->clk);
 }
 
 static int bcm_kp_open(struct input_dev *dev)