armarx/VisionX: Don't treat new warnings as errors

@usnlf_albrecht these new warnings suppressed by this change in Axii is caused by your changes. The warnings were introduced (probably) in GCC >11, maybe 10 or so, didn't test. At least VisionX doesn't build anymore on Ubuntu 22 onwards because of it. (and -Wall unfortunately...)

Maybe you should check clang etc? Clang also complained about this warning.