functionObjects: Removed the redundant "viable" member function

Construction failure and recovery is not handled with exceptions in functionObjectList

src/postProcessing/functionObjects/utilities/writeRegisteredObject/writeRegisteredObject.H

@@ -142,16 +142,6 @@ public:
             const bool loadFromFiles = false
         );
 
-        //- Return true if the construction of this functionObject is viable
-        //  i.e. the prerequisites for construction are available
-        static bool viable
-        (
-            const word& name,
-            const objectRegistry&,
-            const dictionary&,
-            const bool loadFromFiles = false
-        );
-
 
     //- Destructor
     virtual ~writeRegisteredObject();