perf evsel: Use event maps directly in perf_evsel__enable

perf evsel: Use event maps directly in perf_evsel__enable

All events now share proper cpu and thread maps. There's no need to pass
those maps from evlist, it's safe to use evsel maps for enabling event.

Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/1449133606-14429-2-git-send-email-jolsa@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>