vboot: relocate EC and auxfw sync API to 2api.h

Now that EC and auxfw software sync have been updated to
vboot2-style code, relocate function headers to 2api.h.

BUG=b:124141368, chromium:1016688
TEST=make clean && make runtests
BRANCH=none

Change-Id: Iad66b52452a90b13d3ff0ba8b4bced88fa1eb6e1
Cq-Depend: chromium:1973248
Reviewed-on: https://chromium-review.googlesource.com/c/chromiumos/platform/vboot_reference/+/1965925
Tested-by: Joel Kitching <kitching@chromium.org>
Commit-Queue: Joel Kitching <kitching@chromium.org>
Reviewed-by: Joel Kitching <kitching@chromium.org>
2 files changed