ApfFilter: refactor/simplify ipv4 if mMulticastFilter am: 5ecede272b

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

Change-Id: I6b34050b69fe0a4de92dd776662803dd47aa27b9
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>