update comment

direct/src/doc/sample.dc

@@ -58,9 +58,7 @@ struct AvatarObject {
 };
 
 
-// Single inheritance and multiple inheritance are both supported, but
-// to use multiple inheritance you have to (for now) define
-// "dc-multiple-inheritance 1" in your Config.prc file.
+// Multiple inheritance is also supported.
 
 dclass DistributedObjectHolder : DistributedObject {
   dropObject(AvatarObject object);