deploy_termina: pass arch to termina_build_image

Automatically detect the correct --arch argument and specify it so that
deploy_termina works for both amd64 and arm boards.

BUG=None
TEST=deploy_termina to a kevin and verify that Terminal still starts

Change-Id: I84f67182b5a57ea8ed9cc937d1dd1ab24620c12d
Signed-off-by: Daniel Verkamp <dverkamp@chromium.org>
Reviewed-on: https://chromium-review.googlesource.com/1239350
Commit-Ready: ChromeOS CL Exonerator Bot <chromiumos-cl-exonerator@appspot.gserviceaccount.com>
Reviewed-by: Stephen Barber <smbarber@chromium.org>
Reviewed-by: Josh Pratt <jopra@chromium.org>
Reviewed-by: Mike Frysinger <vapier@chromium.org>
1 file changed