crypto: hisilicon/hpre - Fix a erroneous check after snprintf()

This error handling looks really strange.
Check if the string has been truncated instead.

Fixes: 02ab9946 ("crypto: hisilicon - Fixed some tiny bugs of HPRE")
Signed-off-by: Christophe JAILLET <christophe.jaillet@wanadoo.fr>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

drivers/crypto/hisilicon/hpre/hpre_main.c

@@ -1033,7 +1033,7 @@ static int hpre_cluster_debugfs_init(struct hisi_qm *qm)
 
 	for (i = 0; i < clusters_num; i++) {
 		ret = snprintf(buf, HPRE_DBGFS_VAL_MAX_LEN, "cluster%d", i);
-		if (ret < 0)
+		if (ret >= HPRE_DBGFS_VAL_MAX_LEN)
 			return -EINVAL;
 		tmp_d = debugfs_create_dir(buf, qm->debug.debug_root);