Add methods for updating ingressDiscardRule bpf map to BpfNetMaps am: b01647922d am: 1002ddce1e

Original change: https://googleplex-android-review.googlesource.com/c/platform/packages/modules/Connectivity/+/28712473

Change-Id: Iee6925a417ad1d107e8d62f6d15cf92ab24adef6
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>