autotest: Remove references to powerm.

This removes all references to the soon-to-disappear powerm
process from tests.

BUG=chromium-os:36804
TEST=sent to paladin bots.  also ran tests that i changed,
     but most of them fail for unrelated-seeming reasons
CQ-DEPEND=I4640da16879af6d5b54ade0acf1957e112a78153
CQ-DEPEND=I41658fb2dc6f2abb82acb950894a21fee1505001

Change-Id: Ie4b92ea3817405f1b9aa7372bac08122ab30c486
Reviewed-on: https://gerrit.chromium.org/gerrit/41575
Tested-by: Daniel Erat <derat@chromium.org>
Reviewed-by: Chris Masone <cmasone@chromium.org>
Commit-Queue: Daniel Erat <derat@chromium.org>
10 files changed