tools/power turbostat: Always print idle in the system configuration header

If the --quiet option is not used, turbostat prints a useful system
configuration header during startup.

But inclusion of idle system configuration information in this header
is currently a function of inclusion in the columns chosen to be displayed.

Always list this idle system configuration.

Signed-off-by: Doug Smythies <dsmythies@telus.net>
Signed-off-by: Len Brown <len.brown@intel.com>