crypto: mediatek - only treat EBUSY as transient if backlog

The driver was treating -EBUSY as indication of queueing to backlog
without checking that backlog is enabled for the request.

Fix it by checking request flags.
Signed-off-by: Ryder Lee <ryder.lee@mediatek.com>
Signed-off-by: Vic Wu <vic.wu@mediatek.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

drivers/crypto/mediatek/mtk-sha.c

@@ -778,7 +778,9 @@ static int mtk_sha_finup(struct ahash_request *req)
 	ctx->flags |= SHA_FLAGS_FINUP;
 
 	err1 = mtk_sha_update(req);
-	if (err1 == -EINPROGRESS || err1 == -EBUSY)
+	if (err1 == -EINPROGRESS ||
+	    (err1 == -EBUSY && (ahash_request_flags(req) &
+				CRYPTO_TFM_REQ_MAY_BACKLOG)))
 		return err1;
 	/*
 	 * final() has to be always called to cleanup resources