drm/xe: Group live kunit tests

As was done for the normal kunit tests, group the live tests into a
single module, xe_live_test.ko.

Reviewed-by: Rodrigo Vivi <rodrigo.vivi@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20240312145158.2295351-1-lucas.demarchi@intel.com


Signed-off-by: Lucas De Marchi <lucas.demarchi@intel.com>