faft: Skip checking test image in USB when servod runs in a different host

When servod runs in a different host, the original check doesn't work since
we can't access the servo host. Skip the check temporarily such that it won't
break the tests. Should find a way to work-around it.

BUG=chromium-os:34395
TEST=manual, run the following test using Beaglebone:
$ run_remote_tests.sh --board daisy --remote dut \
                      --args "servo_host=dut-servo" RecoveryButton/control$

Change-Id: Ib0c44ca6eec4d17e00d4f85f3c54bd3b5efdf870
Reviewed-on: https://gerrit.chromium.org/gerrit/36211
Commit-Ready: Tom Wai-Hong Tam <waihong@chromium.org>
Reviewed-by: Tom Wai-Hong Tam <waihong@chromium.org>
Tested-by: Tom Wai-Hong Tam <waihong@chromium.org>
2 files changed