iwlwifi: dbg_ini: implement time point handling

Calculate active triggers list and implement time points handling.
Also allow to override the debug domain via iwl-dbg-cfg.ini by setting
FW_DBG_DOMAIN field.

Reported-by: kbuild test robot <lkp@intel.com>
Signed-off-by: Shahar S Matityahu <shahar.s.matityahu@intel.com>
Signed-off-by: Luca Coelho <luciano.coelho@intel.com>