COMP: various compilation changes

- label-size 64 build, compiler warnings, unused template argument,
  faMatrix::clone() method

STYLE: faScalarMatrix - moved info message to within a debug scope

src/finiteArea/faMesh/faMesh.C

@@ -493,7 +493,7 @@ Foam::faMesh::faMesh
     {
         label curMeshEdge = meshEdges[edgeI];
 
-        labelList curEdgePatchIDs(2, -1);
+        labelList curEdgePatchIDs(2, label(-1));
 
         label patchI = -1;