nfs4: Make sure Request::fNext is initially NULL

src/add-ons/kernel/file_systems/nfs4/RPCServer.cpp

@@ -46,6 +46,7 @@ RequestManager::AddRequest(Request* request)
 	else 
 		fQueueHead = request;
 	fQueueTail = request;
+	request->fNext = NULL;
 }
 
 

src/add-ons/kernel/file_systems/nfs4/RPCServer.h

@@ -41,6 +41,9 @@ public:
 
 private:
 			mutex		fLock;
+
+			// Neither SinglyLinkedList nor DoublyLinkedList is what we want
+			// here. And DoublyLinkedQueue is not even a queue.
 			Request*	fQueueHead;
 			Request*	fQueueTail;