dumpstate: stop including "LOG STATISTICS".

The bookkeeping for `logcat -S` is pretty expensive, and it's unclear
that anyone's actually using the resulting data for anything, so as a
first step, let's stop collecting it in bugreports and see if anyone
notices.

Bug: http://b/235157236
Test: treehugger
Change-Id: Id405119e5a8433fa0f8348b687c94596e595a03d