perf utils: Check verbose flag properly

It now can have negative value to suppress the message entirely.  So it
needs to check it being positive.

Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: kernel-team@lge.com
Link: http://lkml.kernel.org/r/20170217081742.17417-3-namhyung@kernel.org
[ Adjust fuzz on tools/perf/util/pmu.c, add > 0 checks in many other places ]
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

tools/perf/builtin-report.c

@@ -1009,7 +1009,7 @@ repeat:
  		 * providing it only in verbose mode not to bloat too
  		 * much struct symbol.
  		 */
-		if (verbose) {
+		if (verbose > 0) {
 			/*
 			 * XXX: Need to provide a less kludgy way to ask for
 			 * more space per symbol, the u32 is for the index on