ApfFilter: refactor/simplify ipv4 if mMulticastFilter am: 5ecede272b am: 2b0e4aaa12

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

Change-Id: Ib3b4d75a9aeabb74e161ee571bfac8dbe3e9e299
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>