Use xt_bpf module to record the iface stats

To make interface packet accounting more accurately and persistent, the
xt_bpf module is implemented to record the total packets and bytes
tx/rx through each interface. The netd will load the bpf program and
set up iptable rules for the xt_bpf module at boot time and the
framework service will use them to get per interface networks stats on
supported devices. Add logcat support to bpfloader program.

Test: iface stats show up in maps. Iptable rules show up after boot.
Bug: 72111305

Change-Id: Ib33d2b165b64e130999931302dd67891c35a12e9
(cherry picked from aosp commit 5ed17991)