futility: Add global args to specify vboot API and format

The host-side futility tool will need to support all extant vboot
implementations. Some legacy futility commands only support the
original vb1 format, but others ("show" or "sign", for example)
may need to be instructed which formats to expect or emit.

This change adds some global args to specify the preferred
formats. It also cleans up a few [unused AFAICT] one-letter args
to avoid conflicts.

TEST=make runtests

Nothing makes use of this yet, except the "help" command.

Change-Id: Ib79fa12af72b8860b9494e5d9e90b9572c006107
Signed-off-by: Bill Richardson <wfrichar@chromium.org>
Reviewed-on: https://chromium-review.googlesource.com/246765
Reviewed-by: Randall Spangler <rspangler@chromium.org>
15 files changed