ANDROID: db845c: Local define for db845c targets

Generally DAMP is a best practice in Bazel, for this
specific case, it helps with:

* Better target discoverability and auto-completion.
* It's possible to use `select` for KGDB fixes later on
  without encountering name expectations broken.

Bug: 256196368
Bug: 270320056
Change-Id: I300404a9b2b4b7c6569145a942ecb445d23e8e9a
Signed-off-by: Ulises Mendez Martinez <umendez@google.com>