tools/power turbostat: Remove SysWatt from DISABLED_BY_DEFAULT

The counter is present on most supporting Intel platforms and provides
useful data to the user. There is no reason to disable the counter by
default.

Signed-off-by: Patryk Wlazlyn <patryk.wlazlyn@linux.intel.com>
Signed-off-by: Len Brown <len.brown@intel.com>