Drop ARP packet in APF if the opcode is unknown am: e63d620672 am: d14fc81c2d

Original change: https://android-review.googlesource.com/c/platform/packages/modules/NetworkStack/+/2840299

Change-Id: Ib7f6f2ed6eb90a382bf35323742e5be71acf97b1
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>