faft: Move PREAMBLE_USE_RO_NORMAL to FAFTSequence

This flag is used frequently. Move it to FAFTSequence.

BUG=chromium-os:34147
TEST=Run the following tests:
$ run_remote_test.sh --remote=$IP CorruptFwBodyA/control$
$ run_remote_test.sh --remote=$IP CorruptFwBodyB/control$
$ run_remote_test.sh --remote=$IP CorruptBothFwBodyAB/control$
$ run_remote_test.sh --remote=$IP SoftwareSync/control$
$ run_remote_test.sh --remote=$IP RONormalBoot/control$
$ run_remote_test.sh --remote=$IP UpdateECBin/control$
$ run_remote_test.sh --remote=$IP ECWriteProtect/control$

Change-Id: I96930dfb4405a3108204054aa74a177042e1d3ec
Reviewed-on: https://gerrit.chromium.org/gerrit/32204
Reviewed-by: Mike Truty <truty@chromium.org>
Reviewed-by: Randall Spangler <rspangler@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 33d0603..46c1860 100644
--- a/server/cros/faftsequence.py
+++ b/server/cros/faftsequence.py
@@ -220,6 +220,9 @@
     VDAT_FLAG_EC_SOFTWARE_SYNC         = 0x00000800
     VDAT_FLAG_EC_SLOW_UPDATE           = 0x00001000
 
+    # Firmware preamble flags
+    PREAMBLE_USE_RO_NORMAL             = 0x00000001
+
     _faft_template = {}
     _faft_sequence = ()