nchstats counters bump

Hello.

With current long type we have abnormal namecache statistics since
type overflow:

189237651 total name lookups
          cache hits (-513% pos + 408% neg) system 25% per-directory
          deletions 12%, falsehits 0%, toolong 0%

Is that possible to commit this, I hope, non-intrusive change (see
attach, not tested)
to tree before 8.x?
It was done in OpenBSD a year ago.

-- 
wbr,
pluknet