Input: ads7846 - use msleep() instead of udelay() in suspend

Sometimes a polling loop had a hard time changing state without
pre-emption enabled. Use msleep instead, it's better anyway.

Signed-off-by: Juha Yrjola <[e-mail]>
Signed-off-by: David Brownell <[e-mail]>
Signed-off-by: Dmitry Torokhov <[e-mail]>

drivers/input/touchscreen/ads7846.c

···
 
 		while (ts->pendown || ts->pending) {
 			spin_unlock_irqrestore(&ts->lock, flags);
-			udelay(10);
+			msleep(1);
 			spin_lock_irqsave(&ts->lock, flags);
 		}
 	}