powertop: upgraded package to upstream 2.8

Upgraded sys-power/powertop to version 2.8 on amd64, arm, x86

BUG=chromium:565988
TEST=`powertop --version` contains string "2.8"
TEST=no functional regressions
TEST=arm: builds

Change-Id: If6c365c9dc574739b8767c004191000be985dc47
Reviewed-on: https://chromium-review.googlesource.com/315884
Commit-Ready: Joe Konno <joe.konno@linux.intel.com>
Tested-by: Brian Wilson <brian.wilson@intel.com>
Reviewed-by: Mike Frysinger <vapier@chromium.org>
3 files changed