Remove dead code in BpfNetMaps.

Most of the methods in BpfNetMaps are only used on T+ devices,
where BpfNetMaps never calls into netd. Remove the code in these
methods that calls into netd, because that code can never run.
The code was only written in the first place because it was
necessary when TrafficController had not yet moved to mainline.

The list of methods is:
- addNaughtyApp
- removeNaughtyApp
- addNiceApp
- removeNiceApp
- setChildChain
- replaceUidChain
- setUidRule

Test: treehugger
Change-Id: Ie7d210be2f7983178f5aa550370b9476de66e988
3 files changed