perf hists browser: Cleanup hist_browser__update_percent_limit()

The previous patch introduced __rb_hierarchy_next() function with
various move direction like HMD_FORCE_CHILD but missed to change using
it some place.
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Cc: Andi Kleen <andi@firstfloor.org>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Wang Nan <wangnan0@huawei.com>
Link: http://lkml.kernel.org/r/1456488800-28124-3-git-send-email-namhyung@kernel.orgSigned-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

tools/perf/ui/browsers/hists.c

@@ -2477,12 +2477,7 @@ static void hist_browser__update_percent_limit(struct hist_browser *hb,
 				     min_callchain_hits, &callchain_param);
 
 next:
-		/*
-		 * Tentatively set unfolded so that the rb_hierarchy_next()
-		 * can toggle children of folded entries too.
-		 */
-		he->unfolded = he->has_children;
-		nd = rb_hierarchy_next(nd);
+		nd = __rb_hierarchy_next(nd, HMD_FORCE_CHILD);
 
 		/* force to re-evaluate folding state of callchains */
 		he->init_have_children = false;