[ctml] Fix constructor for stoichiometric_solid phase
[ctml] Fix constructor for stoichiometric_solid phase

Error introduced in r2579

Heathckliff/cantera,imitrichev/cantera,imitrichev/cantera,Heathckliff/cantera,imitrichev/cantera,Heathckliff/cantera,Heathckliff/cantera,imitrichev/cantera,Heathckliff/cantera,imitrichev/cantera,imitrichev/cantera,Heathckliff/cantera