Restore nPrimVarGrad in InitiatePeriodicComms

Author: paan882

SU2_CFD/src/solvers/CSolver.cpp

@@ -363,8 +363,8 @@ void CSolver::InitiatePeriodicComms(CGeometry *geometry,
 
   auto *Diff      = new su2double[nVar];
   auto *Und_Lapl  = new su2double[nVar];
-  auto *Sol_Min   = new su2double[nVar];
-  auto *Sol_Max   = new su2double[nVar];
+  auto *Sol_Min   = new su2double[nPrimVarGrad];
+  auto *Sol_Max   = new su2double[nPrimVarGrad];
   auto *rotPrim_i = new su2double[nPrimVar];
   auto *rotPrim_j = new su2double[nPrimVar];