CHROMIUM: driver: net: Add latency tracking for ARL

This is a port from chromeos-3.18 to chromeos-4.14-gw of CL:1121779.
(ported from commit b232ebed4d57a8119af30a101551255eb9e02b0c)

BUG=b:138685581
TEST=Latency test with heavy upstream traffic.

Cq-Depend: chromium:1731583
Change-Id: Ide27d74307da4f142cebf981e68de85b84f11bc8
Signed-off-by: Danny J. Mitzel <mitzel@google.com>
Reviewed-on: https://chromium-review.googlesource.com/1731809


Tested-by: Danny Mitzel <mitzel@google.com>
Commit-Ready: Danny Mitzel <mitzel@google.com>
Legacy-Commit-Queue: Commit Bot <commit-bot@chromium.org>
Reviewed-by: Kan Yan <kyan@chromium.org>