leon: Add Leon board to chromeos-bootimage

BUG=chrome-os-partner:22104
TEST=setup_board --board=leon

Change-Id: Ic1414de0cf1e7f85cdd2d3edb9bdb9ba6045608c
Signed-off-by: Steven Sherk <steven.sherk@se-eng.com>
Reviewed-on: https://chromium-review.googlesource.com/167640
Reviewed-by: Shawn Nematbakhsh <shawnn@chromium.org>
2 files changed