autotest: Remove redundent performance tests in network_WiFiSecmat

Each of these tests have an identically named and functionally superior
equivalent in network_WiFiPerf.

TEST=None
BUG=chromium:255244

Change-Id: Id0afeba31204f61caa76a3742a96845a3808a28b
Reviewed-on: https://gerrit.chromium.org/gerrit/60293
Tested-by: Christopher Wiley <wiley@chromium.org>
Reviewed-by: Tan Gao <tgao@chromium.org>
Commit-Queue: Christopher Wiley <wiley@chromium.org>
11 files changed