vboot2: Split vb2_guid into its own header file

This allows the api header to include it without pulling in the rest
of the vboot2 internal structs.

No functional changes; just moving a struct definition.

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

Change-Id: Ife9408f9b597939a3cc85a10d534108e12f2d739
Signed-off-by: Randall Spangler <rspangler@chromium.org>
Reviewed-on: https://chromium-review.googlesource.com/229793
Reviewed-by: Daisuke Nojiri <dnojiri@chromium.org>
3 files changed