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: I708d33596ea3687aaa012fe1b5a46385d68fd6ca
Reviewed-on: https://chromium-review.googlesource.com/c/chromiumos/third_party/edk2/+/7453172
Commit-Queue: Jeremy Bettis <jbettis@chromium.org>
Reviewed-by: Jon Murphy <jpmurphy@google.com>
Tested-by: Jeremy Bettis <jbettis@chromium.org>