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

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

Change-Id: Ie367ea32e5df72ad374b6be25f4d46c43ef82a95
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>