Add ping to IBSS mode tests

Determine what the router IP address is, and allow tests
to ping the router directly if in IBSS mode

BUG=n0ne
TEST=Run both "normal" MatFunc and IBSS tests.  Make sure "router"
parameter fails in non-IBSS

Change-Id: Ic177e335b69699c4220008195d87b6df459e3b6e
Reviewed-on: http://gerrit.chromium.org/gerrit/1937
Reviewed-by: Paul Stewart <pstew@chromium.org>
Tested-by: Paul Stewart <pstew@chromium.org>
3 files changed