This changes how we build and use cbfstool: 1. If build/cbfstool exists, use it. 2. Otherwise, try util/cbfstool/cbfstool. 3. As a last resort, build it and clean it when we're done. Hopefully this will resolve issues people have had with permissions and reduce overhead of building cbfstool when not necessary. Change-Id: I5de6581ca765e5a8420b101a5865ddd633334b9c Signed-off-by: David Hendricks <dhendrix@chromium.org> Reviewed-on: https://review.coreboot.org/12490 Tested-by: build bot (Jenkins) Reviewed-by: Stefan Reinauer <stefan.reinauer@coreboot.org> Reviewed-by: Paul Menzel <paulepanter@users.sourceforge.net>