replace msg::fatal by an error

NonLinearSolver/materialLaw/mlawNonLocalPorousCoupled.cpp

@@ -424,7 +424,7 @@ void mlawNonLocalPorousCoupledLaw::checkCoalescence(IPNonLocalPorosity* q1, cons
   // avoid case with several yield surfaces
   /// why ???
   if (getNumOfYieldSurfaces() > 1){
-    Msg::Fatal("check coalescence has not implemented for num yield surface >1");
+    Msg::Error("check coalescence has not implemented for num yield surface >1");
     return;
   }