Fix the name change of servo_test.py.

It reflects the previous change of the filename in:
http://gerrit.chromium.org/gerrit/5976

BUG=chromium-os:19710
TEST=run_remote_tests.sh --remote=$REMOTE_IP -a \
         "servo_vid=0x18d1 servo_pid=0x5001" firmware_TryFwB

Change-Id: I34dd7766a2a12954e803406bb83eb0dabb5338a8
Reviewed-on: https://gerrit.chromium.org/gerrit/11113
Reviewed-by: Rong Chang <rongchang@chromium.org>
Commit-Ready: Tom Wai-Hong Tam <waihong@chromium.org>
Tested-by: Tom Wai-Hong Tam <waihong@chromium.org>
diff --git a/server/cros/faftsequence.py b/server/cros/faftsequence.py
index 35b1acb..458ba93 100644
--- a/server/cros/faftsequence.py
+++ b/server/cros/faftsequence.py
@@ -11,7 +11,7 @@
 
 from autotest_lib.client.bin import utils
 from autotest_lib.client.common_lib import error
-from autotest_lib.server.cros.servotest import ServoTest
+from autotest_lib.server.cros.servo_test import ServoTest
 
 
 class FAFTSequence(ServoTest):