Add --leave_firmware_alone flag for BIOS testing purposes.

BUG=chromium-os:13100
TEST=none (BIOS team will test by using it)

Change-Id: Ifedeac1a0d13d36a069531bfaba4bdb7b3457406

Review URL: http://codereview.chromium.org/6696013
(cherry picked from commit 192d7e14f6f0991ff1ca53180ad69136fd04570d)

R=puneetster@chromium.org

Review URL: http://codereview.chromium.org/6665059
1 file changed