Add AP team to OWNERS

The process of changing coreboot-sdk-ap-dependencies is very difficult,
because the packages and repos that use it don't have consistent OWNERS.
All of these are used to build AP firmware, and should be owned by the
same team.

BUG=None
TEST=None

Change-Id: I1558d3c1903eacc4b12f58cdf22c29e8b7ca00de
Reviewed-on: https://chromium-review.googlesource.com/c/chromiumos/third_party/edk2/+/7453171
Reviewed-by: Jon Murphy <jpmurphy@google.com>
Commit-Queue: Jon Murphy <jpmurphy@google.com>
Auto-Submit: Jeremy Bettis <jbettis@chromium.org>
Tested-by: Jeremy Bettis <jbettis@chromium.org>