GBT: Do not allow drivers to roll ntime

libblkmaker

@@ -1 +1 @@
-Subproject commit 9f5e949f7e1e0bb49bfe8eab1d99107b3114b4c7
+Subproject commit 28b2ff02304ac8af8a045c26eef46b401ef78d58

miner.c

@@ -2945,7 +2945,7 @@ static bool work_decode(struct pool *pool, struct work *work, json_t *val)
 		int branchcount;
 		libblkmaker_hash_t *branches;
 		
-		if (blkmk_get_mdata(tmpl, buf, sizeof(buf), tv_now.tv_sec, &expire, &cbtxn, &cbtxnsz, &cbextranonceoffset, &branchcount, &branches, GBT_XNONCESZ))
+		if (blkmk_get_mdata(tmpl, buf, sizeof(buf), tv_now.tv_sec, &expire, &cbtxn, &cbtxnsz, &cbextranonceoffset, &branchcount, &branches, GBT_XNONCESZ, false))
 		{
 			struct stratum_work * const swork = &pool->swork;
 			const size_t branchdatasz = branchcount * 0x20;