Add clatd binary to apex

Ship clatd binary with apex. This makes that the clatd binary becomes
updatable.

Bug: 212345928
Test: manual test
1. Connect to ipv6-only wifi.
2. Make IPv4 traffic.
   $ ping 8.8.8.8

Change-Id: I4f6f0944e94e165983a19a5d3c3a117274f6bbac
1 file changed