vboot: Add GBB flag to disable shutdown when lid is closed

This adds a GBB flag which can be used in VbExShutdownRequested
to ignore the state of the lid switch and enable factory to run
with the lid closed.

BUG=chromium:434462
BRANCH=samus
TEST=none in this commit, just adding a new unused flag

Signed-off-by: Duncan Laurie <dlaurie@chromium.org>
Change-Id: Ife93adcc90b2c48e79d4e0c8164d2e64e6326ca7
Reviewed-on: https://chromium-review.googlesource.com/230884
Reviewed-by: Randall Spangler <rspangler@chromium.org>
Reviewed-on: https://chromium-review.googlesource.com/234992
Commit-Queue: Shawn Nematbakhsh <shawnn@chromium.org>
Tested-by: Shawn Nematbakhsh <shawnn@chromium.org>
diff --git a/firmware/include/gbb_header.h b/firmware/include/gbb_header.h
index 8a1b2aa..222a433 100644
--- a/firmware/include/gbb_header.h
+++ b/firmware/include/gbb_header.h
@@ -64,6 +64,8 @@
 #define GBB_FLAG_DEFAULT_DEV_BOOT_LEGACY  0x00000400
 /* Disable PD software sync */
 #define GBB_FLAG_DISABLE_PD_SOFTWARE_SYNC 0x00000800
+/* Disable shutdown on lid closed */
+#define GBB_FLAG_DISABLE_LID_SHUTDOWN     0x00001000
 
 #ifdef __cplusplus
 extern "C" {