perf tools: Add arbitary aliases and support names with -

- Add missing scanner symbol for arbitrary aliases inside the config
  region.

- looks nicer than _, so allow - in the event names. Used for various of
  the arch perfmon and Haswell events.

Signed-off-by: Andi Kleen <ak@linux.intel.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Namhyung Kim <namhyung.kim@lge.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/1352123463-7346-6-git-send-email-eranian@google.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>