Allow MPI_MODE_NOPRECEDE | MPI_MODE_NOSUCCEED for MPI_Win_fence

This combination does not make sense but is not explicitly forbidden by
the standard so remove the argument check for this combination.

cmr=v1.8.2:reviewer=jsquyres

This commit was SVN r31523.

ompi/mpi/c/win_fence.c

@@ -51,9 +51,6 @@ int MPI_Win_fence(int assert, MPI_Win win)
         } else if (0 != (assert & ~(MPI_MODE_NOSTORE | MPI_MODE_NOPUT | 
                                     MPI_MODE_NOPRECEDE | MPI_MODE_NOSUCCEED))) {
             return OMPI_ERRHANDLER_INVOKE(win, MPI_ERR_ASSERT, FUNC_NAME);
-        } else if ((MPI_MODE_NOPRECEDE | MPI_MODE_NOSUCCEED) == (assert & (MPI_MODE_NOPRECEDE | MPI_MODE_NOSUCCEED))) {
-            /* it is erroneous to have both MPI_MODE_NOPRECEDE & MPI_MODE_NOSUCCEED */
-            return OMPI_ERRHANDLER_INVOKE(win, MPI_ERR_ASSERT, FUNC_NAME);
         }
     }