perf intel-pt/bts: Remove unused SAMPLE_SIZE defines and bts priv array

perf intel-pt/bts: Remove unused SAMPLE_SIZE defines and bts priv array

These defines were probably dragged in from sampling support in earlier
patches.  They can be put back when needed.

Signed-off-by: Kim Phillips <kim.phillips@arm.com>
Acked-by: Adrian Hunter <adrian.hunter@intel.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/20170616112339.3fb6986e4ff33e353008244b@arm.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>