ApfFilter: refactor/simplify ipv4 if mMulticastFilter am: 5ecede272b am: 22b8158e8f am: 898e86ccc6

Original change: https://android-review.googlesource.com/c/platform/packages/modules/NetworkStack/+/2857925

Change-Id: Ia03fc8fa9dd43e6b210f8a7886b3b3203f1c1520
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>