modify an error message

src/scheme/HybridHLLRusanovEulerianCompositeSolver_v2.cpp

src/scheme/HybridHLLcRusanovEulerianCompositeSolver_v2.cpp

...HybridRoeRusanovViscousFormEulerianCompositeSolver_v2.cpp

...HybridRusanovRoeViscousFormEulerianCompositeSolver_v2.cpp