Remove dns_adblameinfo from dns_adb

Remove dns_adblameinfo from dns_adb

Keeping the information about lame server in the ADB was done in !322 to
fix following security issue:

    [CVE-2021-25219] Disable "lame-ttl" cache

The handling of the lame servers needs to be redesigned and it is not
going to be enabled any time soon, and the current code is just dead
code that takes up space, code and stands in the way of making ADB work
faster.

Remove all the internals needed for handling the lame servers in the ADB
for now.  It might get reintroduced later if and when we redesign ADB.