s390/zcrypt: Fix AP queue handling if queue is full

When the AP queue depth of requests was reached additional requests
have been ignored. These request are stuck in the request queue.

The AP queue handling now push the next waiting request into the
queue after fetching a previous serviced and finished reply.
Signed-off-by: NIngo Tuchscherer <ingo.tuchscherer@linux.vnet.ibm.com>
Acked-by: NMartin Schwidefsky <schwidefsky@de.ibm.com>
Acked-by: NHarald Freudenberger <freude@linux.vnet.ibm.com>
Signed-off-by: NMartin Schwidefsky <schwidefsky@de.ibm.com>

drivers/s390/crypto/ap_bus.c

@@ -599,8 +599,10 @@ static enum ap_wait ap_sm_read(struct ap_device *ap_dev)
 	status = ap_sm_recv(ap_dev);
 	switch (status.response_code) {
 	case AP_RESPONSE_NORMAL:
-		if (ap_dev->queue_count > 0)
+		if (ap_dev->queue_count > 0) {
+			ap_dev->state = AP_STATE_WORKING;
 			return AP_WAIT_AGAIN;
+		}
 		ap_dev->state = AP_STATE_IDLE;
 		return AP_WAIT_NONE;
 	case AP_RESPONSE_NO_PENDING_REPLY: