Get rid of manual ARP hack in TDLSPing

Instead of plugging in an IP address manually in the TDLSPing
test, set the proper kernel parameters in the interface so the
AP no longer responds to ARP requests for the peer.  This will
be useful to allow us to properly validate that ARP requests
work when TDLS operations are performed against IP addresses.
There's no need to reset these values when the test ends or
starts, since all the devices involved are removed every time
the test starts, and when they get created they return to their
default state.

BUG=chromium:326518
TEST=This is a test

Change-Id: Ia7a11027596bc3b581203e3e211da497f9a3b1fb
Reviewed-on: https://chromium-review.googlesource.com/179271
Reviewed-by: Christopher Wiley <wiley@chromium.org>
Tested-by: Paul Stewart <pstew@chromium.org>
Commit-Queue: Paul Stewart <pstew@chromium.org>
2 files changed