Allow build with Ginkgo but throw runtime error if used with mechanics
Here is a proposition for allowing to build openCARP with Ginkgo, but throw a runtime error if there is an attempt to call init_nl_solver_ginkgo
.
I've copied the structure used for the linear solver to define the function init_nl_solver_ginkgo
, and I've thrown the runtime error the same way it's done on line 37 of SF_ginkgo_solver.cc
.
I think the error messages could be improved. Feel free to modify and merge it as you like.