selftests/resctrl: Split show_cache_info() to test specific and generic parts

show_cache_info() calculates results and provides generic cache
information. This makes it hard to alter pass/fail conditions.

Separate the test specific checks into CAT and CMT test files and
leave only the generic information part into show_cache_info().

Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Reviewed-by: Reinette Chatre <reinette.chatre@intel.com>
Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>