ANDROID: Convert db845c to a mixed build.

* This means using GKI[0] artifacts as base for the kernel.

[0] https://source.android.com/docs/core/architecture/kernel/generic-kernel-image#fragmentation-fix-gki

* It was initially submitted as part of https://r.android.com/q/topic:db845c_mixed_build but then reverted in https://r.android.com/q/topic:revert-2188970-db845c_mixed_build-YESQWWKQCV

* https://android-review.googlesource.com/c/kernel/common/+/2203435

 fixes the previous reason for reverting, making it safe to submit it again.

Bug: 233404531
Signed-off-by: Ulises Mendez Martinez <umendez@google.com>
Change-Id: I18813d34b4b7f9de54c334e47c6478ff235cf37f