We need to define which linear equations solver (MUMPS or SuperLU) to be used in configuration header. This commit adds either of them based on a chosen option and should unbreak the build of cad/gmsh. PR: 288106 Reported by: thierry Approved by: Atanu Biswas <atanubiswas484@gmail.com> (maintainer) Fixes: 5b6b3839ef38 (update to 5.4.4 and take maintainership)