declare variable nDim when defining it

Update Common/src/interface_interpolation/CInterpolator.cpp

Co-authored-by: TobiKattmann <31306376+TobiKattmann@users.noreply.github.com>

Author: maxaehle

Common/src/interface_interpolation/CInterpolator.cpp

@@ -157,11 +157,11 @@ void CInterpolator::ReconstructBoundary(unsigned long val_zone, int val_marker)
 
   unsigned long iVertex, kVertex;
 
-  unsigned long *uptr, nVertex, nElems, iDim, nDim, iPoint;
+  unsigned long *uptr, nVertex, nElems, iDim, iPoint;
 
   unsigned long nGlobalLinkedNodes, nLocalVertex, nLocalLinkedNodes;
 
-  nDim = geom->GetnDim();
+  const auto nDim = geom->GetnDim();
 
   /*--- If this zone has no parts of the marker, it will not participate
    * in the first part of this function (collection). ---*/