tools: perf: Fix typo in tools/perf

Correct spelling typo in tools/perf.

Signed-off-by: Masanari iida <standby24x7@gmail.com>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
diff --git a/tools/perf/util/callchain.h b/tools/perf/util/callchain.h
index 3bdb407..eb34057 100644
--- a/tools/perf/util/callchain.h
+++ b/tools/perf/util/callchain.h
@@ -58,7 +58,7 @@
 /*
  * A callchain cursor is a single linked list that
  * let one feed a callchain progressively.
- * It keeps persitent allocated entries to minimize
+ * It keeps persistent allocated entries to minimize
  * allocations.
  */
 struct callchain_cursor_node {