Input: wm97xx-core - use IRQF_SAMPLE_RANDOM

The touchscreen interrupt is driven by human input which can reasonably
be used to provide entropy.
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Signed-off-by: Dmitry Torokhov <dtor@mail.ru>

drivers/input/touchscreen/wm97xx-core.c

@@ -355,7 +355,8 @@ static int wm97xx_init_pen_irq(struct wm97xx *wm)
 	 * provided. */
 	BUG_ON(!wm->mach_ops->irq_enable);
 
-	if (request_irq(wm->pen_irq, wm97xx_pen_interrupt, IRQF_SHARED,
+	if (request_irq(wm->pen_irq, wm97xx_pen_interrupt,
+			IRQF_SHARED | IRQF_SAMPLE_RANDOM,
 			"wm97xx-pen", wm)) {
 		dev_err(wm->dev,
 			"Failed to register pen down interrupt, polling");