autotest: Move WiFi test bases to server/cros/network/

TEST=Ran check11g successfully.
BUG=chromium:258537

Change-Id: Ifc608c8470d14ee123ce192632172a8b08674e4e
Reviewed-on: https://gerrit.chromium.org/gerrit/61348
Tested-by: Christopher Wiley <wiley@chromium.org>
Reviewed-by: Paul Stewart <pstew@chromium.org>
Commit-Queue: Christopher Wiley <wiley@chromium.org>
16 files changed