Remove unnecessary define UGGRID 0

test/porousmediumflow/2p/cornerpoint/main.cc

@@ -22,13 +22,6 @@
  * \brief Test for the two-phase porous medium flow model on a cornerpoint grid.
  */
 #include <config.h>
-// As of versions Opm 2018.04 and Dune 2.6, using opm-grid and dune-uggrid
-// together results in a compiler error. The following lines enforce that
-// dune-uggrid isn't considered.
-#if HAVE_DUNE_UGGRID
-#undef HAVE_DUNE_UGGRID
-#define HAVE_DUNE_UGGRID 0
-#endif
 
 #include <iostream>