Add option to specify output dir of crosperf

BUG=None
TEST=run crosperf with this option, the results are in the right dir

Change-Id: Id94251c72297f18f275564a1fd1ef0972227ddfc
Reviewed-on: https://gerrit-int.chromium.org/34621
Reviewed-by: Luis Lozano <llozano@chromium.org>
Commit-Queue: Yunlian Jiang <yunlian@google.com>
Tested-by: Yunlian Jiang <yunlian@google.com>
3 files changed