hrtimer: convert s390 to the new hrtimer apis

In order to be able to do range hrtimers we need to use accessor functions
to the "expire" member of the hrtimer struct.
This patch converts s390 to these accessors.
Signed-off-by: Arjan van de Ven <arjan@linux.intel.com>

drivers/s390/crypto/ap_bus.c

@@ -659,9 +659,9 @@ static ssize_t poll_timeout_store(struct bus_type *bus, const char *buf,
 	hr_time = ktime_set(0, poll_timeout);
 
 	if (!hrtimer_is_queued(&ap_poll_timer) ||
-	    !hrtimer_forward(&ap_poll_timer, ap_poll_timer.expires, hr_time)) {
-		ap_poll_timer.expires = hr_time;
-		hrtimer_start(&ap_poll_timer, hr_time, HRTIMER_MODE_ABS);
+	    !hrtimer_forward(&ap_poll_timer, hrtimer_get_expires(&ap_poll_timer), hr_time)) {
+		hrtimer_set_expires(&ap_poll_timer, hr_time);
+		hrtimer_start_expires(&ap_poll_timer, HRTIMER_MODE_ABS);
 	}
 	return count;
 }