Input: smtpe-ts - use msecs_to_jiffies() instead of HZ

Use msecs_to_jiffies(20) instead of plain (HZ / 50), as the former is much
more explicit about it's behavior. We want to schedule the task 20 mS from
now, so make it explicit in the code.
Signed-off-by: Marek Vasut <marex@denx.de>
Reviewed-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>

drivers/input/touchscreen/stmpe-ts.c

@@ -164,7 +164,7 @@ static irqreturn_t stmpe_ts_handler(int irq, void *data)
 			STMPE_TSC_CTRL_TSC_EN, STMPE_TSC_CTRL_TSC_EN);
 
 	/* start polling for touch_det to detect release */
-	schedule_delayed_work(&ts->work, HZ / 50);
+	schedule_delayed_work(&ts->work, msecs_to_jiffies(20));
 
 	return IRQ_HANDLED;
 }