perf/x86/intel/rapl: Cosmetic rename internal variables in response to multi-die/pkg support

Syntax update only -- no logical or functional change.

In response to the new multi-die/package changes, update variable names
to use "die" terminology, instead of "pkg".

For previous platforms which doesn't have multi-die, "die" is identical
as "pkg".

Signed-off-by: Kan Liang <kan.liang@linux.intel.com>
Signed-off-by: Len Brown <len.brown@intel.com>
1 file changed