perf map: Remove extra indirection from map__find()

A double pointer is used in map__find() where a single pointer is enough
because the function doesn't affect the rbtree and the rbtree is locked.
Signed-off-by: Eric Saint-Etienne <eric.saint.etienne@oracle.com>
Acked-by: Jiri Olsa <jolsa@kernel.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Eric Saint-Etienne <eric.saintetienne@gmail.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/1542969759-24346-1-git-send-email-eric.saint.etienne@oracle.comSigned-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

tools/perf/util/map.c

@@ -873,19 +873,18 @@ void maps__remove(struct maps *maps, struct map *map)
 
 struct map *maps__find(struct maps *maps, u64 ip)
 {
-	struct rb_node **p, *parent = NULL;
+	struct rb_node *p;
 	struct map *m;
 
 	down_read(&maps->lock);
 
-	p = &maps->entries.rb_node;
-	while (*p != NULL) {
-		parent = *p;
-		m = rb_entry(parent, struct map, rb_node);
+	p = maps->entries.rb_node;
+	while (p != NULL) {
+		m = rb_entry(p, struct map, rb_node);
 		if (ip < m->start)
-			p = &(*p)->rb_left;
+			p = p->rb_left;
 		else if (ip >= m->end)
-			p = &(*p)->rb_right;
+			p = p->rb_right;
 		else
 			goto out;
 	}