cryptonote_protocol: update target height when syncing too

src/cryptonote_protocol/cryptonote_protocol_handler.inl

@@ -1561,6 +1561,10 @@ skip:
       drop_connection(context, false, false);
       return 1;
     }
+
+    if (arg.total_height > m_core.get_target_blockchain_height())
+      m_core.set_target_blockchain_height(arg.total_height);
+
     return 1;
   }
   //------------------------------------------------------------------------------------------------------------------------