Simplify Cache DB RRset type statistic counters

Ondřej Surý: How much memory would it mean to use 8 bits for rrtypes, and the rest would be a bit field?

That would be: 1 bit for others 1 bit for nxrrset 1 bit for nxdomain 1 bit for stale 1 bit for ancient

That's 8129 values for 13 bits, and 16384 for 14 bits, both are lower then 2^16-1 which we are still using as ncounters.

The arithmetics is currently a brain twister.

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