Refactor site_fmap, flashrom_util and gbb_util module into client/cros.

Change-Id: I69da43763f17189ad8c5c447d4db69e13378b0ce

BUG=chromium-os:12633
TEST=grep the entire autotest repo and find out all source code which has site_fmap, flashrom_util and gbb_util and changed them.

Review URL: http://codereview.chromium.org/6623026
10 files changed