vboot2: use enum hash algorithm

This changes the internals of vboot2 to use the enumerated type for
hash algorithm.  The conversion from crypto algorithm is done only
when unpacking the key (and ok, in checking the rsa padding, but that
goes away in the next change).  This is preparation for the vboot2
data types, which separate signature and hash algorithms into their
own fields.

There is no external change in the calling API to vboot, and no change
to the external data structures.

BUG=chromium:423882
BRANCH=none
TEST=VBOOT2=1 make runtests

Change-Id: I9c6de08d742dab941beb806fbd2bfc1e11c01e2c
Signed-off-by: Randall Spangler <rspangler@chromium.org>
Reviewed-on: https://chromium-review.googlesource.com/225208
Reviewed-by: Daisuke Nojiri <dnojiri@chromium.org>
Reviewed-by: Bill Richardson <wfrichar@chromium.org>
12 files changed