apf: Drop ARP reply if SPA is 0.0.0.0

Some network re-writing packet from broadcast MACs to unicast,
result in this kind of packets cannot be dropped by APF filter.
Thus, drop ARP reply if source IP is 0.0.0.0.

Note: Linux kernel always ignores such replies in the function arp_process().

Bug: 118044271
Test: runtest frameworks-net -c android.net.apf.ApfTest
Change-Id: Id293bf231913d9b483ce7d8dd909e05fa927ccd7