CalculiX and base PaStiX

[3rav]

Please treat this message as information only.

In the development version of PaStiX, some changes have been made to CalculiX, most likely they will be available in version 6.3.0

Changes made (add, CalculiX flag):

"Single allocation coeftab"
"Mixed precision"

https://gitlab.inria.fr/pastix/pastix/-/merge_requests?scope=all&state=merged&label_name[]=CalculiX

[3rav]

Version 6.3.0 are available: https://gitlab.inria.fr/solverstack/pastix/-/releases/v6.3.0

Add mixed precision functionality
- Add Flush-To-Zero an iparm option
- Fix subnormal flush for ARM, added macros and check what version compiles
- Add mixed precision subtasks to convert the right hand sides