2lib: Add gbb flag to enforce CSE sync

The CSE sync process executes a CSE upgrade exclusively when the CSE
version stored in CBFS CSE differs from the current CSE. Given the
infrequency of CSE upgrades, we may not always able to test the cse
sync flow. This patch incorporates a GBB flag, which, when enabled,
enforces CSE sync even if the current CSE version matches the version
in CBFS.

BUG=b:353053317
TEST=Able to build domika

Change-Id: I4d3b56b2bd259ffd6b8b8c57ab35ad6a0f080de9
Signed-off-by: Dinesh Gehlot <[email protected]>
Reviewed-on: https://chromium-review.googlesource.com/c/chromiumos/platform/vboot_reference/+/5718196
Reviewed-by: Yu-Ping Wu <[email protected]>
Reviewed-by: Subrata Banik <[email protected]>
Commit-Queue: Yu-Ping Wu <[email protected]>
Tested-by: Subrata Banik <[email protected]>
Reviewed-on: https://chromium-review.googlesource.com/c/chromiumos/platform/vboot_reference/+/5896363
Reviewed-by: Jayvik Desai <[email protected]>
2 files changed