Add java class for Ingress discard bpf map key value am: 9024892db8

Original change: https://googleplex-android-review.googlesource.com/c/platform/packages/modules/Connectivity/+/28712472

Change-Id: I1533ba07aaa8feda8f908a6a35102e3ebf07492e
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>