use Counter to avoid overflowing an int

cpu/profile.hh:
    use Counter for the profile count to avoid overflow

--HG--
extra : convert_revision : bb603b7d139d1736dced26ef0ce1f93ddea30de7

cpu/profile.hh

@@ -44,7 +44,7 @@ class ProfileNode
     ChildList children;
 
   public:
-    int count;
+    Counter count;
 
   public:
     ProfileNode();