fix typo

OpenFlipper.cc

@@ -140,7 +140,7 @@
        if (check) {
          std::cerr << "Error reopening stdin" << std::endl;
        }
-       ckeck = freopen("CONOUT$", "w", stdout);
+       check = freopen("CONOUT$", "w", stdout);
        if (check) {
          std::cerr << "Error reopening stdout" << std::endl;
        }