ART: Move to using locks.h instead of mutex.h

When only annotating lock requirements, use locks.h.

Bug: 119869270
Test: mmma art
Change-Id: I1608b03254712feff0072ebad012c3af0cc3dda4
diff --git a/runtime/cha.h b/runtime/cha.h
index d1a1b7c..a07ee91 100644
--- a/runtime/cha.h
+++ b/runtime/cha.h
@@ -21,7 +21,7 @@
 #include <unordered_set>
 
 #include "base/enums.h"
-#include "base/mutex.h"
+#include "base/locks.h"
 #include "handle.h"
 #include "mirror/class.h"
 #include "oat_quick_method_header.h"