remove returns after throw

opm/simulators/flow/FlowBaseVanguard.hpp

@@ -206,13 +206,11 @@ public:
         }
     }
 
-
     virtual int compressedIndexForInteriorLGR([[maybe_unused]] const std::string& lgr_tag, 
                                               [[maybe_unused]]  const Connection&    conn) const
     {
         throw std::runtime_error("compressedIndexForInteriorLGR not implemented");
-        return  -1;
-    };
+    }
 
     /*!
      * \brief Extract Cartesian index triplet (i,j,k) of an active cell.

opm/simulators/wells/BlackoilWellModelGeneric.hpp

@@ -105,9 +105,7 @@ public:
                                               [[maybe_unused]] const Connection& conn) const
     {
         throw std::runtime_error("compressedIndexForInteriorLGR not implemented");
-        return  -1;
-    };
-
+    }
 
     int numLocalWells() const;
     int numLocalWellsEnd() const;