fixedShearStressFvPatchVectorField: Removed duplicate "value" entry

Resolves bug-report https://bugs.openfoam.org/view.php?id=2556

src/TurbulenceModels/turbulenceModels/derivedFvPatchFields/fixedShearStress/fixedShearStressFvPatchVectorField.C

@@ -2,7 +2,7 @@
   =========                 |
   \\      /  F ield         | OpenFOAM: The Open Source CFD Toolbox
    \\    /   O peration     |
-    \\  /    A nd           | Copyright (C) 2011-2016 OpenFOAM Foundation
+    \\  /    A nd           | Copyright (C) 2011-2017 OpenFOAM Foundation
      \\/     M anipulation  |
 -------------------------------------------------------------------------------
 License
@@ -125,7 +125,7 @@ void Foam::fixedShearStressFvPatchVectorField::updateCoeffs()
 
 void Foam::fixedShearStressFvPatchVectorField::write(Ostream& os) const
 {
-    fixedValueFvPatchVectorField::write(os);
+    fvPatchVectorField::write(os);
     os.writeKeyword("tau") << tau0_ << token::END_STATEMENT << nl;
     writeEntry("value", os);
 }