crypto: hisilicon/qm - fix judgement of queue is full

The queue depth is 1024, so the condition for judging the queue full
should be 1023, otherwise the hardware cannot judge whether the queue
is empty or full.

Fixes: 263c9959("crypto: hisilicon - add queue management driver...")
Signed-off-by: Hui Tang <tanghui20@huawei.com>
Signed-off-by: Yang Shen <shenyang39@huawei.com>
Reviewed-by: Zhou Wang <wangzhou1@hisilicon.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

drivers/crypto/hisilicon/qm.c

@@ -1647,7 +1647,7 @@ static void *qm_get_avail_sqe(struct hisi_qp *qp)
 	struct hisi_qp_status *qp_status = &qp->qp_status;
 	u16 sq_tail = qp_status->sq_tail;
 
-	if (unlikely(atomic_read(&qp->qp_status.used) == QM_Q_DEPTH))
+	if (unlikely(atomic_read(&qp->qp_status.used) == QM_Q_DEPTH - 1))
 		return NULL;
 
 	return qp->sqe + sq_tail * qp->qm->sqe_size;