BUG/MINOR: dns: don't downgrade DNS accepted payload size automatically

Automatic downgrade of DNS accepted payload size may have undesired side
effect, which could make a backend with all servers DOWN.

After talking with Lukas on the ML, I realized this "feature" introduces
more issues that it fixes problem.
The "best" way to handle properly big responses will be to implement DNS
over TCP.

To be backported to 1.8.
2 files changed