enthalpy calculation according to Driesner 2007 et al: 0-1000degC; 0.1-500MPa (doi:10.1016/j.gca.2007.05.026)
function T_Scale_h_Driesner input SI.Pressure p; input SI.Temp_K T; input SI.MassFraction X_NaCl "mass fraction m_NaCl/m_Sol"; output SI.Temp_K T_Scale_h; output Real q_2; end T_Scale_h_Driesner;