FAFT: Remove the legacy use_pyauto and use_faft arguments

These two arguements were introduced when ServoTest supported connecting
remote PyAuto and FAFT Client RPC servers. Now ServoTest only serves
FAFT Client, meaning that use_pyauto is always False and use_faft is always
True. So remove these arguments.

BUG=chrome-os-partner:21118;chromium-os:215491
TEST=Manual
Ran the affected test cases, firmware_FAFTSetup, on Spring and passed.

Change-Id: I5c740faddb97f81f052e720548bfce8a39b405e3
Reviewed-on: https://gerrit.chromium.org/gerrit/62641
Reviewed-by: Yusuf Mohsinally <mohsinally@chromium.org>
Reviewed-by: Richard Barnette <jrbarnette@chromium.org>
Commit-Queue: Tom Wai-Hong Tam <waihong@chromium.org>
Tested-by: Tom Wai-Hong Tam <waihong@chromium.org>
diff --git a/server/site_tests/firmware_CorruptBothFwBodyAB/control.dev b/server/site_tests/firmware_CorruptBothFwBodyAB/control.dev
index 6d5b099..c9b1d4c 100644
--- a/server/site_tests/firmware_CorruptBothFwBodyAB/control.dev
+++ b/server/site_tests/firmware_CorruptBothFwBodyAB/control.dev
@@ -32,7 +32,6 @@
 def run_corruptbothfwbodyab(machine):
     host = hosts.create_host(machine, servo_args=servo_args)
     job.run_test("firmware_CorruptBothFwBodyAB", host=host, cmdline_args=args,
-                 use_faft=True, disable_sysinfo=True,
-                 dev_mode=True, tag="dev")
+                 disable_sysinfo=True, dev_mode=True, tag="dev")
 
 parallel_simple(run_corruptbothfwbodyab, machines)